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Today I went to launch spellforce when i reached the main screen it's asks me for my serial key What should i do? if anyone can help me i will be forever grateful to you
This question / problem has been solved by Ralackkimage
Did you have the game or a demo of the game installed prior to installing the gog version of the game?
If so you may have left over registry entrys. You will need to uninstall the gog version if thats the case and then clean all traces of the game out of the registry and reinstall it.
i have this same problem, built a new pc, redownloaded spellforce and now its asking me for a serial number(activation code) which i dont have
I had a similar problem after a Windows reinstall. I had copied my games to the new installation (trying to get around reinstalling everything), but Spellforce now asked for a serial number, and refused to let me play.

However, simply reinstalling the game fixed the issue for me. The reinstall also worked in a matter of seconds. Apparently the installer noticed that the files were already there, and just fixed the registry, so that the game didn't ask for a serial any more. Smart. :)
Hi I have the same problem with game asking for a serial number this was a clean install no other versions on the drive ,I have uninstalled and reinstalled it cured it for one time after exiting game and restarting it asked for serial number again help please ^^
Did you all try to start spellforce as ADMIN so that it does not ask for serial number ?
If not start the game as admin and then it should stop asking for a serial number and start normal.
I had the same issue and reached out to customer service. They told me to delete and redownload the game and to run it as an administrator. It worked for a day, then the same problem popped up. My final solution after wasting time trying to fix things was to buy it on steam. Most of the game I purchase on GOG work well, but occasionally I'll buy one that just has major issues.