That's strange. Maybe the .exe file from the witcher2/ bin folder will work? You'll bypass the launcher then.

That's also the error message you would get under certain circumstances if you try to run the launcher when you don't have an internet connection. Are you using a firewall to block access?

The suggestion from Taruni would resolve the problem if this is the cause too.

I spent an incredibly long time removing services from the boot after discovering that it runs in Safe Mode, but I figured out if you just disable the internet adapter, then it will run. I think potentially my problem is that I am on university internet which requires a proxy, and so The Witcher cannot access the web - however im unsure why disabling the network would fix this. Thanks for your help anyway