problem installing modules some work and other not

Hello, I tried to install various modules from admin panel tools>modules

but for some of them (for example groups and membership) the system says Installation of: Groups Failed

instead for others, for example facebook connect the system says

Installation of: Facebook connect Done

why???

thanks in advance

did you install other modules to go with it...   files  photos  sounds videos...   if you click the plus next to the error it should tell you why it failed.

thanks I see and solved

do you know if there is a possibility to upload and the download only for a user a file?

So i administrator upload a file in folder of user and then user (only that user) can download it?

thanks again