Hi folks. Previously unregistered lurker here. I had to sign up so that I could post a HUGE thanks to Cyclone Boom! My sc4 died a few days ago and like many others I suppose, I faffed around to no avail. My gut feeling, due to the behavior and timing, was that it was a windows update that had messed things up. But, who dares wins, they say, I went to the extent of a reformat and re install of win7 (computer is only my boys toy, so nothing on the thing that could be missed). Bingo, after the fresh install of the OS my new install of SC4 worked a treat.......until! Like a fool, I installed all 250MB's worth of the available updates! SC4 died again! I was in the process of finding and eliminating the offending KB update by a painstaking trial and error when I found this thread! Saved me a shed load of time. Removed KB3086255 and hey! All is happy in my little SimCity world! ps. my machine is windows 7 32 bit, so that update effects SC4 on both 32 and 64 versions. Once again BIG THANKS.