EXS 24 Logic Sampler Users Group

Running Logic 5.2.0 on a PC.   

My Exs was working fine and locating the correct sampler 
instrument files for each Logic song until two days ago.
Now I'm unable to click on the menu (inbetween 'edit' and 
'option') within the exs (which usually shows me the contents of 
the samp. instruments folder)
Instead it doesn't bring up any menu.

Also, when I click on 'edit' and a new instrument editor comes up 
I can choose to do a 'recycle convert' it will lay out the parts in the 
midi arrange, but won't associate the correct audio to go with it.  

Again, I can't click on the menu (inbetween 'edit' and 'option') to 
locate any audio to work with the midi parts.  

I've re-installed logic but it is still a problem.  Is there any way of 
resetting the Exs to factory defaults or something to sort out 
where it looks for the files?

All your help is appreciated.

Thanks
Damian