Accesing users accounts?

Is it possible as an administrator to access to the users accounts? I basically had the problem with the avatars dissapearing and now I would like to set them up again, but I prefer to do it myself rather and asking each user to do it. Is it possible? I think passwords are encrypted, am I right so there should be other option?

Deanos Tools includes the ability to access and control accounts through the administration panel. It's a free modification available through the market.

Also in a market you'll can find the Spy admin module