I’d follow up on what the error message suggested. Export your log file, send it to Visual Paradigm support and have them take a look at this. I never experienced this issue myself so I can’t comment on it, other than suggesting that you look out for common problems such as running out of free diskspace.
The easiest way to send the logfile is to go to the ‘Help’ tab and then click on ‘About’. You’ll find the option “Export logfile…” at the bottom of the dialog:
This will open a new dialog in which you’ll be able to save a zip file which will contain all the logfiles involved (VP is a pretty extensive program which consists of and/or uses several individual components). Then just send that zip file to the support team.
That same ‘About’ dialog will also provide you with a link to the VP Feedback page. But I often also use e-mail and simply send that to support at sign visual-paradigm.com, that will also allow you to send attachments (which is just what you need here).
Hope this can help!