I am working in a corporate environment for this issue.
The computer in question is one of 30 computers in the same office that is not currently experiencing this same thing. All connected though the same switch, patch panel, etc. Testing has proven that the switch and line is fine.
We have a server set up for all of the multifunction printers on property and we simply map the printers through this unit.
We have an exchange server for email.
File server... for... files.
Okay, here is the situation. This IBM desktop will be connected to everything, able to print, email, connect to files, etc etc.
Then, or so it seem, will just lose its connection. no email printing etc. She is asked to put in her network credentials again. and usually this works. (it seems that the network dropping out may take up to 3 minuets to fully restore and she tries to put in her credentials too soon).
After each event she is able to restart her computer or type in her credentials and get back to work.. after mapping the printer again.