with a mixture of Windows OSs and a variety of usernames? If so, that sounds fairly typical. If you're connected to a server that authenticates users, this might be by design. Your help desk folks would be the ones to go to if this is causing you problems.
"im connected to my college lan and have vista. sometimes when i click on "network" i do not see all the computers in my workgroup, even though they are visible on other computers, also im not able to access some computers , i get a warning "windows cannot access <folder name>" even though others can access it, pls help