Unable to open attachments

I have a few clients that after upgrading to 2012, when they attempt to open an attachment (varying types of files) the attachment won't open. Application that should be opening is NOT running in Task Manager. Have tried right click and Open or Open with, this will sometimes work and other times not. I found a TID 3356033 for GroupWise 7, is this possibly related?
Please help, users want to revert back to GroupWise 8. Client is running on Windows XP SP3. Server is running GroupWise 12 on SLES 10.