Ipconfig fails in XP

I'm getting this error message folks:

"C:\Documents and Settings\All Users>ipconfig

Windows IP Configuration

An internal error occurred: A device attached to the system is not functioning.

Please contact Microsoft Product Support Services for further help.

Additional information: Unknown media status code.

C:\Documents and Settings\All Users>

Please advise what to do. Owing to this, I could connect using a dial-up connection but was not able to browse any sites, then I thought maybe the dial up is messed up, so I bought hi-speed cable internet, same problem, wouldn't connect. Then I popped the Windows XP Pro CD in the drive and tried a "Repair Install" so that it could replace any missing or corrupt files, still no luck. I had to then nuke the PC, format the HDD with NTFS, and then install XP over it, now finally the internet is working however, I still get the same error message when I type ipconfig on the dos prompt...its driving me nuts!!

Any ideas?!?!

Thanx!
Robin