From Task Manager, you can click File, hold down the Ctrl key and click New Task and that will open a Command Prompt (or boot into Safe Mode with Command Prompt).
Then if you have your copy of normaliz.dll on a USB thumbdrive that is drive D (for example), and XP is installed on your C drive, you could type in something like this:
copy d:\normaliz.dll c:\windows\system32
When the copy completes successfully, you will see a message like:
1 file(s) copied
You can still do it from Task Manager though:
If you are seeing a message like this:
Explorer.EXE - Unable To Locate Component : This application has failed to start because Normaliz.dll was not found. Re-installing the application may fix this problem.
This will be in the Event Log:
Event Type: Information
Event Source: Application Popup
Event Category: None
Event ID: 26
Description:
Application popup: Explorer.EXE - Unable To Locate Component : This application has failed to start because Normaliz.dll was not found. Re-installing the application may fix this problem.
The normaliz.dll file is required for explorer.exe to start. If explorer.exe is not able to run, you will not be able to do much with your system until normaliz.dll is replaced.
You can click OK to the errors and eventually get into Task Manager where you can try to fix it. The message may keep popping up from time to time while you are fixing it, so just click OK to close the message.
If normaliz.dll is missing, you can copy it from a working system to the afflicted system with the same version of XP and Internet Explorer.
You will need to get a good copy and put it on a thumb drive, floppy, etc and copy it onto your afflicted system using Task Manager.
The normaliz.dll file needs to be in the c:\windows\system32 folder and is not a Windows Protected File, therefore when the Microsoft engaged Support Engineer "experts" suggest running sfc /scannow, that is just another one of their wild goose chases that will not work, it will never works and it will only waste your time (and they don't tell you how to run it either - if explorer.exe will not start).
Then the Microsoft engaged Support Engineer "experts" will suggest you expand a copy of the file from the XP installation CD you probably don't have but it is also not on your XP installation CD, and you will have the same problem trying their suggestions to "try" to boot into any kind of Safe Mode, so that will not help you. These "experts" seem to think that booting into Safe Mode or Clean Boot will magically replace missing files, but it doesn't.
You will also not be able to properly run a browser on the afflicted system to get on the Internet to download one.
There is a also great computer security risk in downloading normaliz.dll from some Internet site. The best idea is to get a copy of normaliz.dll from another computer that has the same version of XP and IE and replace it from a USB device (which you can access from Task Manager), or using a working system, you can download one from my SkyDrive.
You can still use Task Manager to run System Restore and that might restore it, but I have never tried it and never use SR anyway.
If you recently did a bunch of Microsoft updates, you may have also gotten IE8 so maybe something went wrong there even though the normaliz.dll is the same for either version.
When you see the error, you can click past it and eventually get to your desktop background image where you can press CTRL-ALT-DEL to launch Task Manager. From TM you can click File, New Task, Browse and change the drop down "Files of type" to All Files so you can see all the files in folders.
Navigate to c:\windows\system32 to see if normaliz.dll is really missing. If the error pops up again while you are browsing, just click OK to get past it. The explorer.exe is trying to run and can't until the missing file is replaced.
If that is the only thing missing, you can get one from a working system of the same type as yours, copy it to a thumb drive or floppy and still using TM, browse, copy and paste it where it needs to be or you can download one from my SkyDrive.
From TM, you can still access your thumb or other even floppy media by browsing, copy, paste, etc all work just fine. You use TM to browse to your thumb or floppy drive, copy the good normaliz.dll and then paste it into the c:\windows\system32 folder where it is supposed to be.
If things get worse, just go back into TM and delete the file to get back to where you were in the first place and continue troubleshooting.
Using a working system, you can also download a copy of the file from my SkyDrive and put it on a floppy or USB thumbdrive and sneakernet it to the afflicted system. Sneakernet means you carry it over to the afflicted system by hand.
I uploaded a copy of the XP Pro SP3 file you need to my SkyDrive (everybody has a SkyDrive for sharing files).
You can download it and when you do, put a copy of the file in these two folders (assuming Windows is installed on your C drive):
c:\windows\system32
Here is the link to my SkyDrive and you can look for the file you need there:
https://skydrive.live.com/?cid=6a7e789cab1d6f39&id=6A7E789CAB1D6F39!311
When you see the files available for download, you may not see the file extension (.exe, .dll, .cpl, .sys, .zip, etc.), but when you download them they will have the correct extension.
When you download the file (especially if you use Internet Explorer), when you get a chance to save the file, your browser may not save the file with an extension (like .exe, .dll, .cpl, .sys, .zip, etc.) so you will have to manually add the proper extension to the file when you download the file before you save it.
You can download the file with no extension and then rename the file to add the proper extension. You don't want to try to use a file called normaliz when the file name really needs to be called normaliz.dll (if the downloaded file has no extension you will have to change the name of the file to add the proper extension to get it to work.
You then need to put the downloaded files in the correct folders on your system.
That may not solve all your issues, but you will at least be past that part and then we can fix the rest.