Would you help us how were the files attached with a PDF file? If you install Reader DC Adobe Acrobat Reader DC Install for all versions are you able to reproduce the issue?
Will be waiting for your response.
The files are PDF Portfolios and some of the files in them are Excel files. It’s xlsm and xlsb files that started being blocked by the 11.0.21 update. we were able to re-allow access by modifying the registry key and changing those types from 3 to 2.
I had the exact same issue, on two different Win7x64 machines.
Before the update, both would open/extract Excel files attached or part of a portfolio.
After the update (11.0.21), BOTH complained about "trust" issues.
On one machine, it was a matter of
1. open xls okay
2. do the update
3. fails to open xls
With about 5 minute between step 1 and step 3.
But I found a solution; it's crazy, but it works:
On an Acrobat.exe or shortcut, select "properties", "compatibility tab", check "run in compatibility mode", and
select "Windows 7" from the OS dropdown.
I am *running* Windows 7, so why do I need to run in Windows 7 compatibility? That's the crazy thing.
After the change, you get a prompt about "always open this type of file?" but you can open the excel attachments.