Could not open 'filename' because it is either not a supported file type or because the file has be

Good afternoon.

I have read the various threads and cannot seem to find an answer to my problem.
I have scanned a file to PDF using a multifunction copier.

The copier then emails the file to me.

I then save it to my OneDrive folder.

From there I attach it to our Accounting software for other users to be able to access.
When I click on the file I can open it.

Other users get the above error.

I have tried printing to PDF and saving that, but with the same result.

I am using Adobe Acrobat Pro version 2023.003.20201.