One Big problem! Help!

[SecretSecretary]

I have created a Half Life 2 mod and did everything the many tutorials say.
I didn't change anything yet, and I just want to launch my mod from Steam.
What happens is it launches, the Valve logo comes up, and the loading screen appears...

Then it just vanishes, and I'm back in Windows!

No error message, nothing!

Everytime!

Please help me! I have been trying to find some problem for days on end,
and now I have absolutely no clue as to what the problem is. I have Hl2
and Episode One as well as the Source SDK and the source SDK base installed. (off course)
I have also rebuilt my mod in visual studio 2005, and I have the client and server dlls in my SourceMod's Bin.
I also did the debugging stuff in the properties in Visual Studio. Nothing seems to make a difference.
I'm sure this must have happened to somebody else before...
Again, please, help me!

 

[fortisvenaliter]

try running half-life 2 (the origional game) and maybe try running hl2dm and hl2eo. Then run your mod again.

 

[SecretSecretary]

Okay, wow, it worked!
Thanks a lot!
Now the only question remains is... WHY?
Would you be so kind as to explain to me
what difference this makes to wether my
mod will run or not? And also, do I have
to run all the half life games EVERYTIME
before I can run my mod? Isn't my mod supposed
to be running independently no matter if
I even uninstalled all my half life games?
This really mystifies me...
Now I'm even more confused.

But thanks a lot!
It's working and there is hope for me!

 

[SecretSecretary]

Okay, arklansman clarified it to me:
"Were you running them for the first time since you installed steam?
If so then it is because steam doesn't transfer the hl2.exe file until
you run the game for the first time."
(on the Mod DB forums)
(forum.moddb.com)

It was also another thing:
I had to change the steamappid in the gameinfo.txt from 215 to 220,
thanks to the advice of EuRoGuy3D.
(on the Mod DB forums)
(forum.moddb.com)

So I had 2 things needed to be done.
You guys can probably imagine how great
and relieved and totally stupid I must feel right now. Thanks!
My Mod is working! It's working!