Hammer randomly crashing apon startup
What I want to say is that I'm also on W7 x64 and always was, so I don't really think this is related to the system, due to the fact that this is a recent problem that appeared like one month ago or so... And even less frequent, it's still there, at least for me...
EDIT
Seriously: I noticed that it crashes a lot much more if Portal2 is running on background. If hammer is running alone then the problem with this crash when attempting to load something tends to disappear... anyone else that can confirm this?
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I've gone to the hammer.exe and set some compatibility mode settings (using windows 7 x64 as well gentlemen).
Right now I've changed it to Vista SP2 + Run as Admin, (not scientific method so I don't know if just using run as admin will help).
Anyway, I've tried to reproduce the error a few times (open dialog blank freeze), hasn't happened.
hammer.exe is in the portal 2 bin folder, give it a shot, see if it helps 
I'm on W7-64... so what you suggest is to run the tools in compatibility mode? (ofc I'm running it as administrator, but in normal mode...). Because this past weekend it has crashed attempting to open a file like 20 times!!! 
I was about to grab my mouse and the keyboard (that btw don't have anything to do here, they're innocent!!) and throw them throughout the fu***n window!!! (... my God, they are innocents! and I was about to kill them!!! arghhh... shame on me!! 
)....
I've been trying boosting the game with GameBooster (stopping unnecessary processes to speed the game up)... but apart from running more smoothly, it didn't make much difference agaisnt the crash...
useful tools and stuff here on TWP [spoiler]
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Sorry for bringing back a dead post, but now I can't even go 30 seconds without it crashing. If you're Steam friends with me you'll see this isn't an exaggeration, I have to keep relaunching the Authoring Tools.
According to Task Manager, RAM use slowly climbs until it crashes. And the bin folder is filled with core dumps from when asserts apparently failed.
Even GameBooster can't get it to work for longer tn 27 seconds, which is ridiculous. I can't even edit an entity's properties in that time.
Yes, and it now works. I'm not sure why, but unlinking the HL2 files from where Hammer was looking somehow made it run faster. Does it cache information about everything or some such? I wasn't using any of the HL2 content...