Hello,

I'm writing this information here because I have noticed that the information distributed on this issue is not very good. So I wanted to put the solution here, for future references and hoping it will show up when people facing the same problem are searching google or this forum.

The problem was the following :
After installing Mandrake 10.0 and Windows NT on my computer, during startup of Mandrake "bringing up eth0" failed. The internetconnection was working fine in Windows, though.

Now, when searching google I encountered a great deal of discussions on this matter, but no clear-cut solution. When actually it turned out to be quite simple.
In a sort of I-don't-have-a-clue-anymore-mood I typed "ipconfig/release" in my command line in Windows NT and rebooted under Linux. And voila, everything was working great.

I am wondering though: why did this work ?
Keep in mind that I am just an amateur, and am completely dependent on the information distributed on the net (as are most of the computer users I imagine).
Did this sollution work because the modem remembers what ethernetcard I am using, and since Windows claimed thad card before Linux, it wouldn't let me use that card onder Linux ? We use a belgian internet provider "Telenet", and I know for a fact that the modems they use won't let you switch ethernetcard, which has caused me problems in the past. (If this doesn't make any sense, forgive me, I said was an amateur).