I wanted to player Anno 1602 (GOG Version) again, but i end up with weird colors ingame.

I wrote a batch to kill the explorer, but it didn't help.
Also tried pressing the pause button twice while in main menu, but also didn't fixed the problem.

Any ideas what i can do?

i fixed it by using dxwnd.exe, an emulator that handles old directx games.
However, would be great to find another solution :)

Better use the DDraw compat dll here rather than dxwnd. (although it may work decently).

That did not work for me, unfortunately.

Did you put it in the same directory that the 1602.exe ?

yes

Strange, it worked for me. Can you provide a screenshot or 2 of how the game looks ingame and during a video ?
Are there some compatibility settings set for the exe ? If yes, try removing them.
Is there a ddraw.log file that has been created in the same directory ? If yes, is there some error message in it ?

Try another version of the dll like this one and see if it works better.

Thanks alot for your reply after all these time went by :)
But meanwhile I left Windows and switched to Linux (Ubuntu) where the game runs fine.
Still, thanks for you answer and help, I hope this will help other users to get rid of the problem!