jie[at]outlook.com

Jie.

In the previous blog post I mentioned the following:

Should I use slipstreamed SharePoint server installation files to deploy SharePoint and its CUs?
Maybe – depending on if you want to use language packs or not. If language packs are not installed when you install SharePoint Server, and you install those LPs after the server has been installed, you may need to reapply SharePoint CU packages to get all those LPs up to date.

Now I got questions about this “maybe”. Let me go deeper in this topic…Slipstream is good – but you have to use it in the right way, with the right order.

A typical slipstreamed SharePoint Server install is like this:

1. Install SharePoint Server RTM + SP1 + June CU Slipstreamed
2. Install SharePoint Server Language Packs
3. Run PSConfig

Looks simple and clear. But it is wrong – you will have RTM version of Language packs in this way. Why? Think about the table we had in previous post, then think about Cumulative Update concept. If something is not installed when you apply the CU package, then those files of the missing component will not be installed at all. In this case, the language pack updates in the CU server package are the ones missing. 

The following screenshot shows what this will look like (Chinese LP in 4763 RTM, but all other components are in June CU 6105)

To fix this issue you need to apply language pack SP1s and June CU again. So the installation order should be changed to something different:

1. Install SharePoint Server RTM + SP1 + June CU Server Package Slipstreamed
2. Install SharePoint Server Language Packs
3. Install SharePoint Server LP SP1(s)
4. Install June CU Server Package again
5. Run PSConfig

This would work. But why install June CU twice? It’s a waste of time so let’s change it again. The other thing is that you can slipstream LP SP1 into language pack installation files (extract and put all files in updates folder):

1. Install SharePoint Server RTM + SP1 Slipstreamed
2. Install SharePoint Server Language Packs + Server LP SP1 Slipstreamed
3. Install June CU Server Package
4. Run PSConfig

Now all language packs are updated to latest version.

What can you learn from this? Don’t slipstream CU if you need to install additional language packs. Always apply CU Server Package at the last step.

Jie.

There’re always lots of questions around SharePoint patching. How to patch SharePoint? Which patch should I use to get a certain build number? In which order should I apply those patches? What is CU? What is SP? What is the difference between them?… All these questions are hard to answer – because to understand the answers, you have to understand the patching process of SharePoint.

Let’s go through different scenarios of SharePoint patching. Hopefully this can explain the mystery. I will start with the easy one and then the complex one.

Apply a security/feature fix on SharePoint Server Farm

This is the most simple scenario in SharePoint patching. Download the patch, apply it to every SharePoint Server in the farm and run PSConfig on all of them. That’s it.

Wait, is this really that simple?

The answer is no. Because there will be quite a few questions here:

• Will my database be updated?
  Maybe. Depending on which DB version you have right now, a DB schema may or may not be triggered.
• When will the database be updated?
  If a database schema update is necessary, then the first time you run PSConfig those databases will be updated. Alternatively you can detach all content databases, apply the patch, run PSconfig, and then reattach content databases. In this way you can choose when to update individual content databases.
• How can I tell if this patch can be applied to my farm?
  Take a look at the build number. SharePoint patch will check the version number to decide if a file should be replaced or not. If you already have a component with a higher version number, then it will not be touched since all the fixes are already included.
• How can I know what is included in the patch?
  Aha! Now you get the point. I’m going to share my secret here, you may have never seen this before on any official documents.
  
  Look at the KB article of the fix. There is a file information table which contains all MSI/MSP/CAB filename, size and date. The following quick table may help you to understand the names:
  
  

  Directory Name	File Name	Component
  SharePoint Server 2010
  ACCSRV	acsrvwfe	Access Services
  DLC	dlc	Document Lifecycle Component
  IFS	ifswfe	Infopath Forms Services
  LHPSRV	lhpwfe	Slide Library
  OSRV	osrv	Shared Components
  MEWA	mewa	Excel Mobile Viewer Component
  PPL	pplwfe	User Profile
  PPSMA	ppsmawfe	PerformancePoint Services
  SEARCH	oschwfe	Search Server 2010 Core
  SPS	spswfe	SharePoint Portal
  VISIOSERVER/VisioSrv	vsrvwfe	Viso Services
  WASRV	wasrvwfe	Web Analytics
  WDSRV	wdsrv	Word Server (Word Automation)
  WSS	sts (wss)	SharePoint Foundation 2010 Core
  XLSERVER	xlsrvwfe	Excel Services
  SharePoint Foundation 2010
  WSS	sts (wss)	SharePoint Foundation 2010 Core
  Office Web Apps 2010
  WACMEWA	wacmewa	Office Web Apps Excel Mobile Viewer
  WACWFE	wacwfe	Office Web Apps Web Front End
  WOSRV	wosrv	Office Web Apps Shared Components
  XLSERVERWAC	xlwacwfe	Excel Web App Components
  Project Server
  PRJSRV	prjsrvwfe/pswfe	Project Server Web Front End

  
  Table 1. All Components in SharePoint 2010 Related Products
  
  File names ending with “MUI” means MUI/Language Pack for that component. For example dlc and dlcmui, sts and wssmui, etc. Ending with -x-none means it is not language related.
  
  It is very important to understand the above table – if you really want to get clear on patching, you may want to recite it . Anyway, sometimes the description provided on KB pages are not correct. For example https://support.microsoft.com/kb/2516497 says it is a Office Web Apps hotfix package in April. And here’s the file table:

Wdsrv-x-none.msp
Not Applicable
44,946,432
17-Mar-2011
22:59

Use my table above to look up the component, you will find WDSRV does not belong to Office Web Apps, but SharePoint Server 2010. It is the Word Server (Word Automation) component. Someone mistakenly labeled it Office Web Apps hotfix. So, if you tries to apply this update to a SharePoint Foundation + Office Web Apps installation, it will never work – because this WDSRV component does not exist. If you applied any SharePoint Server update that has a higher version number than this patch, it will not be able to be applied either since the fix is already included.

Is this helpful? Let’s go on to the second scenario: Cumulative updates.

Apply Cumulative Updates/Service Packs on SharePoint Server Farm

CU packages are released in a bi-monthly manner. We want to make it more predictable so customer can plan their patching window, and save time by package everything together. CU does not have the same testing quality with Service Packs in theory, and the release schedule is always a little bit funny. Most of the CUs are scheduled to be released at the end of that month (subject to change), for example Apr CU was released on Apr 26th. If a last minute regression comes in at that time, then the release will be delayed, and you may already noticed Feb CU was released in March 3rd, to ensure the quality.

I used to post CU release information on SharePoint Team Blog. Now Stefan Goßner’s blog is my favorite to catch up with all the information. For example his Apr CU post is quite clear on the packages: https://blogs.technet.com/b/stefan_gossner/archive/2011/04/27/april-2011-cu-for-sharepoint-2007-and-2010-has-been-released-today.aspx

You can see he listed all the full server packages. Please remember, unless necessary, please only use these server packages to apply CU update. Internally we call them “Uber” updates, which includes all language packs and all components. If you are not using these packages, you may be missing some component updates. How to tell that? Using the table above to compare with the file information tables in KB article, and you will find all of the components are covered, with all MUI packages. Individual fixes do not have all of them.

Service Packs are different. Traditionally the service pack downloads does not give you an all-in-one package like the Uber updates do. Language packs are not there in the main package, you need to download and apply them separately.

Now here are the questions:

• Do I need to install SharePoint Foundation CU first to update a SharePoint Server farm?  【Please follow SharePoint Team Blog/TechNet guidance to apply the patches at this moment】
  No. SharePoint Foundation CU are included in SharePoint Server CU packages. Look at the table I showed you above, STS.CAB is all what Foundation has, and that is already included as part of SharePoint Server 2010 and its CU/SPs. Apply Foundation CU before a SharePoint Server CU won’t break your farm, just a waste of time since the setup program has to go through those files twice.
• Should I use slipstreamed SharePoint server installation files to deploy SharePoint and its CUs?
  Maybe – depending on if you want to use language packs or not. If language packs are not installed when you install SharePoint Server, and you install those LPs after the server has been installed, you may need to reapply SharePoint CU packages to get all those LPs up to date.
  
  Best way to install a up-to-date multi-language SharePoint Server 2010 farm now is
• Install SharePoint Server 2010 with SP1 Slipstreamed
• Install SharePoint Server 2010 Language Packs with SP1 Slipstreamed
• Install Office Web Apps 2010 and Project Server 2010 with SP1 Slipstreamed if necessary
• Install SharePoint Server 2010 (with Project Server 2010) latest CU Full Server Package
• Install Office Web Apps 2010 latest CU (if exists)
• Run PSConfig

All the above is just to identify which update should be installed. The best “how to patch” article is still the one on TechNet: https://technet.microsoft.com/en-us/library/ff806338.aspx and it covered how to monitor patching, how to reduce downtime, etc.

Jie.

When Chris Givens was working on 10174 training course he noticed that the uninstall did not go smoothly as he thought. I was working with him and reviewing the content as the content owner from a Product Manager’s perspective, and got notified as well. However a lot of things happened afterwards so I didn’t have time to look at it until now.

Here’re a few points you must remember when you want to uninstall Office Web Apps:

• Uninstall Office Web Apps will remove the server from the SharePoint Farm. If you read the notification carefully when you click the uninstall button you will know this.
• All web applications and sites created by SharePoint will be deleted from IIS.
• You can rejoin the machine back to the Server Farm by psconfig with your farm passphrase.
• You need to redeploy customizations to the server.
• If this happens to be the server which hosts Central Administration, you need to rebuild the CA. This can be done through the Management Shell: New-SPCentralAdministration -Port xxxx -WindowsAuthProvider "NTLM"

If you can tolerance server down time then maybe it’s fine for you. Otherwise the whole process are not that pleasant. So how about just disable it like this:https://technet.microsoft.com/en-us/library/ee837418.aspx ?

To deactivate the Office Web Apps Feature on a single site collection by using Windows PowerShell

Using Notepad, open a new text file and then copy and paste the following script into the file.

$webAppsFeatureId = $(Get-SPFeature -limit all | where {$_.displayname -eq "OfficeWebApps"}).Id 
$singleSiteCollection = Get-SPSite -Identity https://<site_name> 
Disable-SPFeature $webAppsFeatureId -Url $singleSiteCollection.URL

Hmm, in fact this will not completely disable the feature. You have to enable “Open in Client” feature as well, then all files can be opened in Office clients instead of the browser. However if you visit the server without Office client installed or using something like Safari/Chrome, you will still be redirected to the Office Web Apps page like WordViewer.aspx even you have deleted the service applications, stopped the related services.

Why? Because the modification to the drop down menu and open behavior by Office Web Apps cannot be turned off using those ways. Of course, a full uninstall will work – but like what I listed above, it has many cons. Luckily this is not the end of the world. With a few hours work I identified the change made by Office Web Apps and confirmed with the product team. Here’s my findings:

The reason why you can see those drop down menus with items like “Edit in Browser” is because the XML definition is changed. Take this one as an example:

c:\program files\common files\microsoft shared\web server extensions\14\template\xml\serverfilesword.xml

Content:

<?xml version="1.0" encoding="utf-8" ?>
<!-- Copyright (c) Microsoft Corporation. All rights reserved. -->
<ServerFiles>
    <Mapping FileExtension="doc"  RedirectUrlTemplate= "/_layouts/WordViewer.aspx?id=|0" NoGetRedirect="TRUE" />
    <Mapping FileExtension="dot"  RedirectUrlTemplate= "/_layouts/WordViewer.aspx?id=|0" NoGetRedirect="TRUE" />
    <Mapping FileExtension="docx" RedirectUrlTemplate= "/_layouts/WordViewer.aspx?id=|0" NoGetRedirect="TRUE" CreateRedirectUrlTemplate= "/_layouts/CreateNewDocument.aspx?id=|0" />
    <Mapping FileExtension="docm" RedirectUrlTemplate= "/_layouts/WordViewer.aspx?id=|0" NoGetRedirect="TRUE" CreateRedirectUrlTemplate= "/_layouts/CreateNewDocument.aspx?id=|0" />
    <Mapping FileExtension="dotx" RedirectUrlTemplate= "/_layouts/WordViewer.aspx?id=|0" NoGetRedirect="TRUE" CreateRedirectUrlTemplate= "/_layouts/CreateNewDocument.aspx?id=|0" />
    <Mapping FileExtension="dotm" RedirectUrlTemplate= "/_layouts/WordViewer.aspx?id=|0" NoGetRedirect="TRUE" />
</ServerFiles>

The purpose of this file is to tell SharePoint that if it has such doc files within a doc lib, use the redirect url template to process it. So what we will do is to simply remove this file or comment out the section to make it looks like this:

<?xml version="1.0" encoding="utf-8" ?>
<!-- Copyright (c) Microsoft Corporation. All rights reserved. -->
<ServerFiles>
<!--
    <Mapping FileExtension="doc"  RedirectUrlTemplate= "/_layouts/WordViewer.aspx?id=|0" NoGetRedirect="TRUE" />
    <Mapping FileExtension="dot"  RedirectUrlTemplate= "/_layouts/WordViewer.aspx?id=|0" NoGetRedirect="TRUE" />
    <Mapping FileExtension="docx" RedirectUrlTemplate= "/_layouts/WordViewer.aspx?id=|0" NoGetRedirect="TRUE" CreateRedirectUrlTemplate= "/_layouts/CreateNewDocument.aspx?id=|0" />
    <Mapping FileExtension="docm" RedirectUrlTemplate= "/_layouts/WordViewer.aspx?id=|0" NoGetRedirect="TRUE" CreateRedirectUrlTemplate= "/_layouts/CreateNewDocument.aspx?id=|0" />
    <Mapping FileExtension="dotx" RedirectUrlTemplate= "/_layouts/WordViewer.aspx?id=|0" NoGetRedirect="TRUE" CreateRedirectUrlTemplate= "/_layouts/CreateNewDocument.aspx?id=|0" />
    <Mapping FileExtension="dotm" RedirectUrlTemplate= "/_layouts/WordViewer.aspx?id=|0" NoGetRedirect="TRUE" />
-->
</ServerFiles>

Then do the same to serverfilespowerpoint.xml. Unless you are using standard CAL, there’s no need to touch Excel Services since it’s a part of Enterprise CAL and is not installed by Office Web Apps.

Then combine this change with the disable of Office Web Apps feature and the enable of Open in Client feature, Office Web Apps can be disabled completely on the site collection from a user experience perspective. You can also stop the related services and service applications.

Jie.

Screenshot of the original page:

Okay, the first one is KB2346411, and the second one is KB2345015. And it further stated in the bulletin that For Microsoft Office Web Apps, customers need to install both security update KB2346411 and security update KB2345015 to be protected from the vulnerabilities described in this bulletin. Fine. So apply KB2346411 – pretty straight forward, no restart or psconfig needs to be run. Then, apply KB2345015 – here comes the problem. You may see a strange dialogue show up like below:

Aha, an empty box with OK button. OK for what? Click…

Huh?

I didn’t install any other updates except KB2346411 for Office Web Apps. So now this is really confusing – if this so called “Security Update for Microsoft Word Web Application 2010” is try to apply a fix for Word Web App (Apparently they even made the product brand name wrong, but anyway, some times they even called SharePoint Foundation 2010 as Office SharePoint Foundation. They have no respect of our brand names), then it should update some files related with Word Web App, which I had never patched before. Background knowledge: CU fix does not include Office Web Apps. Now it tells me the update is already “installed” – this made me nervous about my system security. Is it patched? Or is this something wrong with that fix?

After reading into the description of the KB article, it turns out the files it want to replace are the WDSRV.DLL related ones. This is Microsoft.Office.Word.Server in your GAC. Let me explain – this is not Word Web Apps at all – it is not even a part of Office Web Apps. Instead, this is Word Automation Services, which is used to convert word documents on SharePoint Server. Further explanation is here: https://msdn.microsoft.com/en-us/library/ee558830.aspx. This component is included in all SharePoint Server installation even without Office Web Apps installed. And this patch, is already included in December 2010 Cumulative Update so there’s no point to apply it if you have Dec CU already.

Quick Summary: If you need to apply MS10-079 to a farm with Dec CU, the only thing needed is KB2346411.

Jie.

What? The input control is disabled? Current License shows I have SharePoint Server with Standard Client Access License, it’s not a trial, so it’s not my key problem.

When move the mouse to the input box, it shows a default cursor, instead of a text cursor, which means it is disabled. I tried inside and outside the VM, different browsers, nothing really help.

I don’t have the time to troubleshoot what the hell happened, so here’s the trick:

Get your IE8 developer tool out, and point it to the disabled input box.

Now you can have the line highlighted. Hmm, disabled=”disabled”. Let’s change it to trick the page.

I changed the name “disabled” to something that doesn’t make sense. I guess people can have a better idea for this but anyway.

Now I can input my Enterprise license key to the box. Wait, OK button is still disabled. Time for the same trick…

After Ok button is enabled, click on it, the feature for Enterprise CAL now can be unlocked without any problem.

I don’t know what caused the original problem. But anyway, this is a quick way to have a workaround.

Note: this is not for production use. If you got the same issue on a production farm, better call support.

However, some of the information there may not be accurate…or just confusing. So I will try to make it clear in this post…

Here’re some questions I collected during the past months, and the answers to them are based on my experience, not official support statement:

Can Mac users use SharePoint 2010?

Of course yes. Both Safari and Firefox are supported browsers of SharePoint 2010 because of the introduce of XHTML 1.0 in the product. The limitations can be found in https://technet.microsoft.com/en-us/library/cc263526.aspx. However, there’re some mistakes in the language used in the article so please read on.

Can SharePoint Admins manage SharePoint 2010 with Safari?

Central Admin web site can be accessed by Safari and Firefox without any problem. If you do have issues with OOTB Central Admin site, please check settings on your Mac and network – something is wrong there, not SharePoint. There’s no ActiveX controls to block you from doing any admin tasks. Of course, there’s no Windows PowerShell on a Mac so you cannot do the Windows PowerShell Remoting tasks, but that cannot stop you from using Remote Desktop for Mac to connect to those SharePoint Servers.

Can I directly open Office file from SharePoint and save it back?

Yes, although you will not have Read Only/Edit option to choose from before you open it in Office for Mac. The file will be opened as Read Only by default, and you can modify the file by click Edit. Then you can also save it back to the original location.

Can I upload file to SharePoint using Mac?

Certainly you can. In the TechNet article there’s an item like this:

File upload and copy: Requires an ActiveX control that is not support on this platform.

But this is invalid. File upload does not require an ActiveX control. What you cannot achieve is to use the Upload Multiple Documents options, see below.

Can I upload multiple files to SharePoint using Mac?

On the browser, no. Unless you use virtualization solutions with Internet Explorer, the Upload Multiple Documents menu item is disabled. The reason behind this is the feature requires STS Upld ActiveX control. However, you can use Microsoft Document Connection to upload multiple files without any problem.

Microsoft Document Connection, which was introduced in Office for Mac 2008 SP2, now is also a part of the Office for Mac 2011 installation. It can connect to both SharePoint sites and SkyDrive. Multiple file upload is simple with this application – just drag and drop them into the application then everything is done. The application itself can be seen as a very lite version of SharePoint Workspace, although it doesn’t do much beyond upload, read, edit, check in/check out. You cannot delete a file, create a new folder, or edit its metadata properties in this app, and to get the latest update you need to hit Refresh button.

Can I have Explorer View in Mac?

No. Since how Windows/Mac plus all the browsers has different ways to handle this protocol, it is nearly impossible to have a standard way to implement it to work across different platform with native Explorer/Finder support.  Microsoft Document Connection is a good client to replace this feature.

How do I use Infopath/Onenote/Access/Visio, etc…on SharePoint with Mac?

Since these applications are not existing in current Office for Mac 2011 release, the only way to use them on Mac is to use virtualization. Alternatively, you can use Infopath Service, Onenote, Access Service and Visio Service on SharePoint with Safari/Firefox on Mac. Office Web Apps also allows you to directly view/edit Office files without even install Office for Mac on the machine. (You need to have a Office client license to use Office Web Apps on SharePoint)

Does Media Web Part work on Mac?

Yes. You need to install SilverLight on Mac before it’s functional.

Can I insert HTML5 video content to SharePoint so it can work with Mac?

Yes. Upload the video to any document library and reference it in your video tag. Please note H.264 content will not work with Firefox since they didn’t implement the support. See https://blogs.msdn.com/b/opal/archive/2010/06/14/what-s-the-story-for-html5-with-sharepoint-2010.aspx

Here’s an example: The upper right video is from Media Web Part, while the lower left one is built with Content Editor Web Part with HTML5 <video> tag.

Since I have already installed Office for Mac 2011, can I use the features on the Ribbon such as Connect to Outlook, Excel, SharePoint Workspace, etc?

Unfortunately no. These features uses ActiveX controls except Export to Excel. And for Export to Excel feature, since Excel for Mac does not have a good support for Web Query(.iqy), it is really hard to make it to work. I may need to dig into the details, but it seems like when you run saved query Excel failed to authenticate with SharePoint.  Outlook for Mac does not have the ability to connect to SharePoint.

Can I edit SharePoint pages using Safari? I cannot do it with iPad or iPhone!

Yes you can – This is fully supported. The mobile version of Safari is a trimmed down version of Safari -- it does not support contentEditable property so it cannot be used with any rich text editing application. For details see https://blogs.msdn.com/b/opal/archive/2010/09/01/can-i-use-ipad-iphone-with-sharepoint-2010.aspx

Is there presence support if I installed Communicator for Mac?

No. The presence information (green/yellow/red) is shown through an ActiveX control installed by Communicator(Lync) if you use Windows. But you can have presence indicator when you use Office clients such as Outlook for Mac.

I’ll try to update this post when I have more information…

Jie

[11/13/2010] +Moprise is a new free SharePoint client on iPad - it handles files pretty good, but lacks of ability to handle lists.

Disclaimer: This is not an official support statement or recommendation from Microsoft Corporation and SharePoint team.

In the last blog post I discussed iPad experience on SharePoint but didn’t go through the Apps, so this blog is to continue the discussion. Please note this is not even a personal recommendation, just a quick reference to help the readers to consider when they want to do the similar. And as always, 3rd party applications should be supported by their developers, not Microsoft.

If you do a search for “SharePoint” on iPad’s App Store, you can find two generic SharePoint clients. One is Filamente and another is SharePlus. There’re some other special SharePoint clients around, like a NewsGator client and a Team Portal client, we are not discussing them because they only work with their own platform.

So, what’s the difference? I bought both apps, and played with them for over a month. It’s interesting to see both of them provided a good set of features, and SharePlus also have a lite version for people to try out… Really hard to say which one is better. Here’s a quick table of the facts from my experience. I only work with some list items and document sets on our SharePoint library so this does not cover all the area.

*I bought SharePlus at 4.99USD in Sep. SharePlus Lite is free all the time without list items editing feature.

Performance

Just personal – it feels like Filamente is faster than SharePlus when you try to open a SharePoint site and load all asset list. But after that the two are the same.

UI and Features

The two Apps shares a similar UI with minor difference. But the lack of document set support in Filamente is really annoying. Other than that it’s fine. In v1.1 Filamente added FBA support, I haven’t got a chance to try out though.

Preview

Both of the Apps use Apple’s default viewer which means bad formatting for office documents. But both of them allows you to open the file in a 3rd party App which may handle the formatting better. Neither of the Apps use Office Web Apps even that’s deployed.

Don’t expect these apps to be able to handle all the collaboration scenarios on SharePoint. But if you just want to preview the documents and lists on the iPad, they are pretty handy compared with the browser experience in Mobile Safari.

Jie.

https://www.microsoft.com/technet/security/bulletin/MS10-070.mspx

You may have already read these articles. If not, please do it right now.

https://www.microsoft.com/technet/security/advisory/2416728.mspx

https://blogs.msdn.com/b/sharepoint/archive/2010/09/21/security-advisory-2416728-vulnerability-in-asp-net-and-sharepoint.aspx

I will not repeat the message in those posts, but you should follow the instructions to prevent potential attacks.

So how about SharePoint Server 2007 and WSS 3.0? It’s not on SharePoint Team Blog (yet).

You may need to follow the workaround for ASP.Net 1.0~3.5:

• Put error.html in %CommonProgramFiles%\Microsoft Shared\Web Server Extensions\12\template\layouts
• Modify web.config in each directory under %SystemDrive%\inetpub\wwwroot\wss\virtualdirectories to have a customerror section like this: <customErrors mode="On" defaultRedirect="/_layouts/error.html" />
• IISRESET /NOFORCE

Update: 2007/WSS3 is not vulnerable to the attack. No workaround is needed right now, but you still need to apply the fix when it come out.

Please follow the updated SP team blog post for 2007 issue:

https://blogs.msdn.com/b/sharepoint/archive/2010/09/21/security-advisory-2416728-vulnerability-in-asp-net-and-sharepoint.aspx

How to validate? Can I type in some non-existing pages to test if web.config changes work on SharePoint?

The answer would be no. When you try to access a non-existing page on a SharePoint site with a modified web.config you will still have 404 codes. But SharePoint has its own custom error handler to generate those 404s for non-existing pages, which will not be able to be used directly by the attack. The workaround will be able to prevent error codes from being generated by accessing certain ASP.Net resources, and it would work if you followed the steps correctly.

Just remember, the ultimate solution is the upcoming ASP.Net fix. This workaround is just temporary, get you protection before the patch is released. Once it’s released, apply the fix and then restore your web.config to the original ones.

Jie