red X’s in my network places

Why is it that when I go to “My Network Places” sometimes everything has a red “X”. If it is a mapped drive, I just click it and the x goes away and I am connected. Also, what am I doing to cause folders to show up there, but when I click on them I see two files: target and desktop.ini.

We are still a NT 4.0 domain with more and more Win2K clients if that means anything.