GIT - gitk and git bash won't open anymore on windows 7 -

i used open git bash right-clicking directory (i'm on win7 64), today doesn't work anymore (the console pops second , disappears).

i still able use git bash inside phpstorm terminal, , if issue gitk command there, i'm getting following error

m.allocationbase 0x0, m.baseaddress 0x68550000, m.regionsize 0x4e0000, m.state 0x10000 e:\program files (x86)\git\bin\sh.exe: *** couldn't reserve space cygwin's heap (0x68550000 <0x24b0000>) in child, win32 error 0 

git version:

git version 1.7.8.msysgit.0 

these git bash , gitk daily tasks perform tons of times day, since years. broke without apparent reason. help?