Weird - and maddening - PowerPoint problem

Backbiter

Whenever I try to save a new PowerPoint 2010 presentation to a specific folder, the Save dialogue box freezes. And eventually I get the message 'PowerPoint has stopped responding' and it restarts itself, but on restart the file I was working on does not show up in the Restored Documents and is lost forever.
The only workaround is to just click Save in whatever Default location appears in the dialogue box, and then move it manually to the folder it needs to go in .
The problem is I keep forgetting about this fault and keep losing work.
I have reset the 'Save Autorecover' option to every 1 minute, but the file is never there when the programme restarts.
What the hell is causing this and how do I fix it?

Pthree

I had this issue (I installed it as a stand alone so not sure if that makes a dofference) but removing and reinstalling seemed to fix the problem.

P3

Backbiter

Thanks - will try that. It's actually on a PC at work so I'll have to get a technician to do it.
It's not happening with Word or Excel, although I have had quite a lot of problems with Excel crashing and losing data I was working on, so a reinstall seems like a good move.