pdf file will not open after being downloaded thru eM Client

All PDFs sent to me and downloaded thru eM Client will end up corrupted and unable to open.  I see there was a problem in the past but no remedy for it happening today.  
Current Version: 7.1.31849.0

I think there have been a few issues in the past with some incompatibility with certain servers and attachments. Which email provider is this with? 

Also, maybe try downloading and installing the latest version at https://www.emclient.com/release-history

Updated to latest load as of today: 7.1.32792.0  and "repair"ed my inbox.
Still has same issue.

I use IMAP (imap.mail.att.net) and SMTP (smtp.mail.att.net) for servers.

I don’t remember AT&T being one of the problem servers. Don, if you have a Pro License, you could open a support ticket for this. I am sure they will be able to assist you further.