This file is the executable for an electronic billing service. We have run this .exe file before but now it will just not run on any of our machines, either as current user or as administrator (both local administrator and domain administrator). Tried iot on local machine logon as well as domain logon. Compatibility wizard couldn't fix it. Not blocked by AVG. Firewall turned off. Permissions seem to be in order because all other .exe's on the system will run and install perfectly. Program is running on 2 other computers on which it was installed several months ago but trying to run this downloaded file is driving me nuts. BTW, we have 3 different downloads of this file. The older one is a different size than the newer downloads but none of the .exe's will run on any of 4 machines I have tried. Can you help?