A question: Do you have ever installed GP4 on your HDD before or a long time ago?
If, yes, you have to uninstall your game properly and to clean your registry with ccleaner before to make a fresh install. For me, it looks like a dll is missing or a conflict with previous files installed.
If no, several things to check:
1- Both Gp4.exe (nocd) & gpxpatch.exe must be ran as administrator and in compatibility mode with Windows xp SP3 ( it can run without but it is better to avoid crashes or compatibility conflicts)
2- with the CD insert message, do you see another message with bink.dll or bink32.dll file missing? If yes: check this thread and Mortal's message: [
www.grandprixgames.org]
3- Try with this working nocd: I have used it since years and with several re-installations: [
www.mediafire.com] (don't forget to set run as admin and compatibility mode)
In general, into the installation process, once the game, official patch and no cd is installed, you have to launch the game once (not necessary a race but until the menu) , save and quit before to install GPxPatch.
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