Steam problems: Hl2/HL2DM locks up at the 'Loading…'-Screen

Just thought about sharing this tiny bug fix:
So here is our situation, we got steam uptodate, all graphic driver updates, same for motherboard, etc, all fixed and running but for some reason hl2, hl2 dm and other source games keep locking up at the “loading…” screen. The menu just doesnt show up. Same happens if you join a server directly.
The core problem is related to your automated firewall in xp/2000.

First of all quit steam. Dont have it running!
Check if this service is running by pressing windows-key (the one with the windows flag on it) and r at the same time. You will get a box saying “run” or “ausfuehren (german)”. Enter “services.msc” without the quotationmarks, and press enter. You will get a window showing your services or dienste. Scroll down to “windows-firewall and shared internet use” and right click on it to see the properties. In any case, shut down the service and re-enable it. If you didnt have it running, start it. Now start steam again. Windows will probably ask you whether you want to grant access internet access to “steam.exe” or not. Of course you want.
Then select say HL2 DM and start it. Same question will appear just with HL2lexe. Accept it and grant access.
Magically it will work. The menu will show up and you`ll see all your source games working. Enjoy. If you have questions or comments, feel free to enter them below. As the steampowered forums and their faq?s stink and dont work for anyone, use this place to get your stuff running.