I am running version 5.5.1022 on a Vista Home Premium 64 box. In the past when I received a update notice I downloaded the update or upgrade and installed it on top of the prior version (Without Issue). I was on your Web site an noticed version 5.6.1010 and attempted to installed it and ran into the following issue. The new program ran and asked to uninstall version 5.5.1022 and failed with a error "Application failed to start version.dll not found". This locked up my PC and the only way to recover it was a hard reboot. Trying to uninstall version 5.5 from add or remove programs caused a message “Error reading uninstall data". I was able to close out of this error, without restarting. This happens with version running or shut down in the task bar. Otherwise the program updates definitions, run scans without issue. How do I effectivly remove the old version and upgrade to Ver 5.6??