Portal doesn't run after compiling
First of all, I'm new here, so first I will introduce myself shortly. (if it's in the appropiete in this section)
I'm Timo Aaldriks, from the Netherlands (so i'm sorry if I have incorrect grammer) I fell in love with portal as soon as I saw the trailer, and never regretted the purchse of it. I'm really new to the Source SDK, but this site and others already helped me al lot 
So here's my problem:
I made a simple map in hammer, and tested it a few times. But suddenly it doesn't run after compiling. It gives no errors or anything. it start's up the loading page, and suddenly it crashes, and Windows says there's a problem and portal had to shut down 
Does anyone ever had a problem like that before?
Check Don't run game after compiling. Compile it and open Portal. Open console with (~/`) and type "map mapname" Make sure you save the map in ...portal/portal/maps. If that does not work, it is your machine. Old PCs don't run hammer as good as a PC meant for gaming. Trust me. I use to make maps on a DX 7 graphics card computer.
The more you give, the less appreciated it will be received.
Also, trying running Portal once manually, then exiting the game, then compiling again - Portal should now run.
This occurs at times; when an update doesn't fully kick in I believe...
What I do is what Taco said; run Portal manually which should set things back in order when you do a compile and run.
"Imagination is everything. It is the preview of life's coming attractions." -Albert Einstein
that always works for me. and almost everytime it doesnt run i run it manually then it says updating portal or something then it works.
Thanks for the reply's, but it didn't help 
If I start the game manually, I hear something bounce against metal, and then it just shut's down again. So i'ts not that portal doesn't run (I made a wron title maybe) it just loads, and crashes as soon as it should be playable.
Other maps run normal so I think it's something inside my map that causes the problem, but i don't know what it could be 
maybe try resaving your map file to another file name then compile .. i dont know if it will work but try everything.
Nope, doesn't solve anything, but thanks anyway
ummm.. thats really strange. maybe.. download vmex and decompile your last version of the bsp.. than start working from there. then at the things that isnt in that version you can copy that from the broken file.. hope you understand what i mean
check your map for problems in hammer.
try to remove entities one by one (especialy prop_physics entities), these could have caused the bounce against metal you described.
other than that, no clue...
(percentage calculation sphere self-test failed!)
108.1% done, -8.1% remaining...
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