In another posting, I wrote that one of my laptops was sending me a message that said "Microsoft.NET Framework has encountered a problem and must close." I tried uploading the SP1 for this program but can't get it to load. This is preventing AC 4.0 from loading on this machine. I looked in the software removal area and see that there is currently Microsoft.NET Framework 1.0 and 2.0 loaded. What do I need to do? Pray? Thanks Dave