HD2 - Steam version CD key problem - possible fix!

I installed the game with the original discs and legal key

Right so same as me.
And do you have STEAM installed on your pc?

no steam intalled on my pc

Okay, so Pat experiences no problems with the "key already in use" message, but I do.
Only difference between him and me is the fact I have STEAM installed and he doesn't.
If I am correct Pat also uses windows 10 64 bit, like me.

Actually, I have window 10 64 bits and I have never had any notifications "keys already in use"
Steam Generates Key Errors? Maybe

I really want to test out my retail version of the game with another steam user later, after I uninstalled my steam version.

I believe my retail key also clashes with steam users and i dont know why. And my retail key starts off with 15a0-767e-****-****, so its totally different compared to the steam key which starts with 1234-5678-****-*****

I need someone with 2 mins to spare a bit later to connect to a server im on with a steam version to see if the cd key error comes up even with my retail key. Since at the moment, i keep changing my steam version to my retail key. But its not helping, I have the feeling my retail key "15a0-767e-****-**** doesnt work either if someone is using the steam version on the server. :o

So im gonna just uninstall the steam version for now since i dont know if something is wrong with my registry. Dont know why i get cd key in use error when playing with my retail version with the retail key showing in registry. Dont know if its because i also have steam version installed and its changed something elsewhere. So I will just uninstall everything completely, and just do a fresh install of my retail version afterwards.

Then hopefully someone can try to test to play with me with a steam version. and see if its still popping out cd key in use errors. :o

Since then i know, that theres no point changing the steam version key to my retail, if it still wont let me play with other steam players. :o