Does your issue only happen with LU, or does single-player give you this problem now too?

It only happens with LU, no problem on single player game.
I don't have a steam game, I have a CD version, so it shouldn't be a problem.
However I have WinXP sp2, so I will try with sp3 to see if it works better.
Thanks for your help, I would be so happy to be able to do multipayer game in GTA3!

No modding at all. I've just tried a trainer but nothing else, no modification in the data files.
One more thing, when I install the updates of LU (as it is asked to me at the first launch), LU doesn't works anymore, it says something like : "the enter point of process GetLogicalProcessorInformation is not findable in the library of dynamic links KERNEL32.dll" (translated from french).
But it works when I don't let the updates be downloaded.
I think this is because I'm on winXP.
Are the updates really necessary to make it work ?

I've tried what you two proposed me, but it didn't change, there is the same kind of screen and the same message. Do you have other ideas ?

Hello.
I've installed Liberty Unleashed, but when I run the game (whatever the server), I always get this screen on :
I've tried with the gta3.exe NO-CD one, and also with the original one (but version 1.1) with CD. Still the same.
Could someone help me?
Thank you very much.