session saving problem

Hopefully I'm in the right forum for this:
I'm having a problem with saving sessions. I had multi previously and 
was very happy with it  but  had added an extension  to moz suite 1.7.8 
that could not be removed. Had to delete moz and reinstall. Now multi is 
not working the same as before. When I close a window it used to ask in 
a small window if I wanted to save the session, yes or no. Now half the 
time it doesn't ask and just overwrites. The rest of the time it asks in 
a session like window if I want to overwrite, add new, or skip. I can 
live with that If I have to but not the blind overwrite. I'm using 
1.7.9.0a (1810 crashes moz). This is the same version I was using before 
as I still had the download. I've tried checking and unchecking boxes 
galore! Can anyone help me with this or tell me the correct forum to go to?

Thanks,
Lynn