Occasional corrupt pdf attachments in email

Is anyone else occasionally having an LBI report delivered to a users delivery device as an attachment that they cannot open because of 'Adobe Reader could not open <insert-report-file-name.pdf> because it is either not a supported file type or because the file has been damaged (for example, it was sent as an email attachment and wasn't correctly decoded).

This has been plaguing our users occasionally just about since we came up on LBI.

Anyone have any suggestions as to how to solve it?

I've reported it to GSC now about 3 times, and they never really do resolve it.

Thanks anyone,
-Greg