ok, well yesterday hammer was working absouloutly perfectly! Then just this morning i opened it up to continue on my map and it started installing updates. When the updates had finished i opened up hammer and opened my map, it looked like this: 
as you can see the top left hand corner is blank why is this? ive reinstalled it and tried making new maps but it stays the same and my colours are set to the highest possible! help me!
the whole sdk!
edit: refreshing sdk diddnt help
Hmm, You said Hammer was working fine the day before WITHOUT updates, then you loaded up Hammer this morning and now its updating...thats odd, cause if by "this morning" you mean within 24 hours before you posted this thread....I have not recieved any updates from Steam. Did the updates specify what they were for, and i imagine they were official steam updates, yes?
Edit: I am reading on the Interloper's error page here.. and they say it might be because of "drivers or other interfering soft/hardware" Might wanna look into that?
