Hello, I'm having a rather strange problem currently...

Since my computer didn't have the best internet connection I decided to upgrade it and installed a new mainboard, new hard disks and a new network chip.

Anyway, after I installed Steam I installed Worms Reloaded. Whenever I try playing it Steam tells me "Worms Reloaded is not available at the moment, please try again later".

I reinstalled it about five times and it just doesn't run. I haven't got a clue at all why this is happening. Anybody knows what to do?

This has happened a fair number of times to people so there are a fair few discussions out there about it, this is the most likely fix: http://forums.steampowered.com/forums/showthread.php?t=854102

? This description doesn't help me. I can't find "Regional and language options" anywhere, neither an "advanced" option. Can anybody here explaint it to me a little exactlier?

? This description doesn't help me. I can't find "Regional and language options" anywhere, neither an "advanced" option. Can anybody here explaint it to me a little exactlier?

It's referring to the Control Panel in Windows which is accessed through your Start menu. Start > Settings > Control Panel > Regional and Language Options (on Windows XP at least).
I think the logic behind this is that changes to your system such as you have made reset certain things and thus confuse Steam. I recently upgraded my motherboard too and had similar problems.

I need someone to explain me this in German.

I'm failing at the first point. I really can't find "settings" because that would be "Einstellungen" in German. Too bad that word doesn't occur anywhere so they must have named it differently.

Alright, I did it, but I still can't play the game. Other suggestions?

some generic steam fixes:
Restart steam
Verify integrity of game cache (right click game, click properties, then local files)
Delete the clientregistry.blob (located in the same location as the steam exe) then restart steam
Delete local files and redownload the game

I'd try them in order.
Deleting the clientregistry.blob is pretty much the do all, end all solution to nearly everything on steam.

Deleting the clientregistry.blob is pretty much the do all, end all solution to nearly everything on steam.

This. It requires you to log in again after doing it, but it fixes most major problems. For me, it occurs when I make changes to my hardware (as you have done).

Didn't help. Also, this is what Steam told me to do - I tried everything but still no success:

1. Exit and restart Steam
2. Update All Drivers - including DirectX, PhysX, and Visual C++ as found at the bottom of the guide
3. Exit Steam and rename the ClientRegistry.blob and restart Steam
4. Exit Steam and delete everything under the Steam installation directory except Steam.exe, the ClientRegistryOld.blob, and the \SteamApps folder - this will force Steam to update when you log in
5. Complete the Verifying GCF Cache Files process to repair your game cache files.
6. This error may be caused by having certain Steam files set to Read Only. To resolve this:

* Exit Steam.
* Navigate to the directory where you have installed Steam. (Typically C:\Program Files\ or C:\Program Files\Valve\.)
* Right-click on the Steam folder.
* Select Properties.
* Check the Read-Only checkbox and press Apply.
* Uncheck the Read-Only checkbox and press Apply.