Desktop version blocked .pdf attachment but 365 version did not

Question

I was using Outlook (desktop version on Windows 10 Pro) and received an email from someone listed in my contacts with a .pdf attachment however, the attachment was blocked. The message said "Outlook blocked access to the following potentially unsafe attachments: image001.png, image002.png, NOD.pdf.

The images are part of the signature block and not important but the .pdf attachment being blocked is a problem. I use the desktop version everyday at work and this has never happened so I asked IT how to "unblock" the attachment and was advised to log into the 365/online version. Surprisingly (or maybe not), the attachment and the images were fine.

Does anyone know why this happens and how to prevent it in the future?

I guess I will be adding this to my reminder list of "use the desktop version for these tasks and the 365/online version for those tasks."

** On a side note if anyone has figured out why when searching (all Outlook items for example) you get different search results from the desktop version and the online version, I'd like to know.

Answer 1

Thank you.

Do you know why search results are usually different for desktop and OWA?

For example, if I am looking for an old email and type ABC123 in the "Searched In" box and set it to search "All Outlook Items" and any defaults (if applicable) are the same, why do I usually get different results in desktop vs. OWA and is there a fix for this?

Answer 2

Thank you. Am I to understand that the desktop version has security features that the OWA does not?

Do you know why search results are usually different for desktop and OWA?

For example, if I am looking for an old email and type ABC123 in the "Searched In" box and set it to search "All Outlook Items" and any defaults (if applicable) are the same, why do I usually get different results in desktop vs. OWA?

Answer 3

Very Good morning MsEaglesFan,

I hope you are doing good and thanks for your reply ,

Let me try to elaborate again for your more understanding. Over to your question : Frist thing first some functionality are different in ( Outlook DESKTOP client VERSION vs. Outlook web access (OWA) 365/ONLINE version ).

As we can see your pdf is not getting block by (OWA) whereas outlook client showing error. I have mentioned previously your attachment getting block by Outlook client due to security features ,however this security check cannot be done by Outlook web access (OWA) 365/ONLINE version [ Therefore you don't have any problem to open your PDF attachment on online ]

Additionally I have already shared how to disable this feature including all related KBs , You may check internally.

 Sincerely,

Amul | Microsoft Community Moderator

Answer 4

I understand the security features but that is not the issue nor is the sender or what was sent.

My issue is DESKTOP VERSION vs. 365/ONLINE version of Outlook. One blocked the other did not block.

Perhaps I'm not explaining this well but I'm sure how much simpler I can make it. When using the DESKTOP version the pdf attachment was blocked however, when I used the 365/ONLINE version the attachment had no issues and opened as it should. I was on the same computer on the same network, etc. ....there was nothing different other then which version of Outlook I used.

I have found other issues like this where the desktop version gives you result X and the online/365 version gives you result Y. I've just never had it happen with a pdf attachment. Why does this happen and is it fixable?

Answer 5

Dear MsEaglesFan,

Good day ,

Thanks for posting in Microsoft Community.

I understand that you had an concern where your outlook blocked your attachment however now it's working fine. Yes, I have gone through your case's description and based on your mentioned scenario with error msg "Outlook blocked access to the following potentially unsafe attachments" I would like to share related information as below :

All versions of Outlook since Outlook 2000 Service Release 1 (SR1) include a security feature that blocks attachments posing a risk of viruses or other threats. Microsoft has official article to check complete information including troubleshooting steps moreover I am sharing the URL with you for your future reference : https://support.microsoft.com/en-us/topic/outlook-blocked-access-to-the-following-potentially-unsafe-attachments-c5c4a480-041e-2466-667f-e98d389ff822 

Also it's also possible to disable this Outlook feature through a Regedit key, which wouldn't be that advisable in terms of security

If someone having this with specific sender then It could be fix by this way : Add recipients of my email messages to the Safe Senders List

Also , It If you don’t use an Exchange Server account, there is an advanced procedure that you can use to unblock some file types. File types blocked in Outlook

NOTE : For your security and privacy , kindly don't mention any email address / password or other confidential information.

We look forward to your response. Thanks for your cooperation.

Sincerely,

Amul | Microsoft Community Moderator

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