From the first look this error definitely sounds like “Office 365 ATP Safe links or Safe attachments” policy components blocking the files behind the scenes, but it’s not !. Well, it could be the same error in such scenarios but in my case, Safe Link or Safe Attachment policies were not the issue.
Scenario: Users trying to share content within the organization by uploading them to a OneDrive/SharePoint location chosen from the dropdown as attached to the Outlook email on the go.
Attach a file to email and upload it to OneDrive/SharePoint
Attach a file from SharePoint/OneDrive
Once added the cloud based file to the mail, this is how it looks. Then send it out
Emails are smoothly delivered to the recipients however, when they try to open them (by simply clicking on the URL), recipients get the above error (The page that you are trying to access cannot be loaded)
This happens only when:
- Users use desktop application of Outlook (not happening in OWA, files are accessed in OWA without an issue)
- Or, Attached the file in to OneDrive or SharePoint as shown below (not happening when file URL is pasted to Outlook email)
The environment had Office 365 ATP safe link and Safe attachment policies implemented properly. And the exceptions are added to trusted partners across the globe for this company (as a multi-national)
Resolution: Due to the criticality of this organization-wide behavior, I worked with Microsoft Support team towards a fix and here’s what we did.
We ran a fiddler session while opening the file from both OWA and Client App and reviewed the recording – OWA is working fine while outlook not able to access the wrapped URL. It looked like outlook API used for calling ATP is not functioning well.
Microsoft further analyzed by collecting below information and then engaged the Product Group:
- Collect fiddler trace for both OWA and Outlook to make comparison
- Copy the Wrapped URL from OWA and Outlook
- Collect the corresponding message sample
As of now, Microsoft Product Group for ATP have not identified if it is a misconfiguration or product related bug, however, I receive constant responses stating that they are actively working towards a resolution. I will update this space as soon as I hear anything applicable towards a resolution/ETA.
Workaround: The only workaround for this is to request users to make use of Outlook Web whenever a file needs to be opened that is received via an email.