You might try this:Disconnect from internet,open Impulse and then go to preferences(top left,blue orb or lightening bolt,whichever you have).Click on preferences and then on "Reset Data".Close Impulse,reconnect to Internet and then run Impulse.

I really hope they add the ability to disable Impulse's auto-updating in the future,if possible. I prefer to choose when to update things.

Hum, I updates all my apps this morning with impulse and I have IE8, and all the security crap on. Ah, vista ultimate.