CAD performance deterioration, commands don't respond

[cat3appr]

Hello,

 

I'm noticing a general deterioration of my Autocad 2014:

my main problem is that I can't open files from FILE/OPEN , the window does come up, but then when I click on Look in / specific folder, the folder pattern gets blank, it doesn't show anything.

Then, I try to do any other action and CAD doesn't respond at all..

 

anyone can recommend where shall I try troubleshooting?

 

thanks!

[ReMark]

Is this a networked or standalone computer?

 

When did the problem first occur?

 

Have you made any changes to the hardware or software?

 

Are you running any custom lisp programs?

 

Have you tried to reset settings to default?

 

Have you tried a REPAIR of the installation (this is NOT the same as an uninstall/reinstall)?