I run Windows 7 on a core i5 laptop 1 year old. I've purchased Grime fighter, read the email for downloading and start-up, but the program hangs at the restart of the computer. The start-up screen hangs on the application of the anaesthetic with the green bar stuck at 60%, then nothing. I have been pestered to purchase this program by avast for the last half year and as I have found that the usual software works excellent, Grime fighter is a big disappointment. I see from the forum I am not the only one with this problem so it would be good to get some help to correct it please. Does anyone know if it is also covered by the 30 day refund as with the premier program?