Excel Open File - Security Warning for our own company SharePoint site, followed by network share

Question

I received a ticket from a single user who was receiving a security warning when opening an xlsx file on one of our SharePoint libraries. I added our SharePoint site to trusted locations in the domain group policy, which fixed the warning for files in that library. Now Excel started showing this warning for xlsx files in our network drive (W:) when it hadn't previously. I performed the same steps and added this network drive to trusted locations in the domain group policy and confirmed the user's PC did grab the new policy, but this time the warning persists.

Looking at other posts about this issue, and assuming this user is the only person receiving these warnings as no one else has raised this concern, I tried a few things on her local PC:

1. Enabling 'Launching application and unsafe files' under the security tab in Internet Options.
2. Adding the W drive to trusted locations in the Excel desktop app. The app would NOT allow this location to be saved.
3. Manually adding the trusted location in the Excel desktop app via Registry. It does appear in the Excel trust center but is greyed out.

Answer 1

Hello,

 

Thank you for posting in Q&A forum.

To fix this issue, please kindly try below steps:

1.Go to Excel Trust Center Settings, and add the SPO site to trusted in the browser or via GPO for all users. You need to make sure “Check Microsoft Office documents that are from or link to suspicious Web sites” option is properly configured.

2.Go to Internet Options -> Security -> Trusted sites and add the SPO site to check if it works.

 

I hope the information above is helpful.

If you have any questions or concerns, please feel free to let us know.

 

Best regards，

Jill Zhou

 

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