'''THANK YOU FOR POSTING THAT''' Exactly the same scenario with us-- we were doing fine with Firefox until we installed the '''premium trial version of Malwarebytes''' anti-malware. Frankly, if this is the best Malwarebytes can do, we do not plan to use the application. Just imagine actually paying for this poorly-tested betaware! Malwarebytes had a fairly solid reputation until some sort of butchered internal reorganization last year. After that, the marketing hype began-- indicated by a change in advertising graphics to the "Malwarebytes Killer Robot', and other adolescent antics. Prices went up, quality plunged-- typical fallout from yet another attempt at transformation from the top. And a gentle reminder that quality takes time, not advertising. For us, it's goodbye to all that with Malwarebytes, and we'll use whatever means we must to rip the application out by its misbegotten roots. Hopefully, we'll post our complete experience with removal of Malwarebytes, but at the moment, the application's own option to uninstall in Windows "Add/Remove" does not work beyond initial stages, when it simply stalls, leaving a grey box where the "Remove" button lies. Examining the thread with SysInternals' Process Monitor, we found the uninstall thread cannot be terminated ("Error opening [filename.tmp]-- Access Denied")-- which makes sense, because our removal parallels what malware might try. But that means we must download the Malwarebytes uninstall tool-- https://support.malwarebytes.com/docs/DOC-1168 Unfortunately for us, the latest MB uninstaller simply stalls, and MB instructions provide no hint about obstructions to uninstallation. We found Revo Uninstaller was helpless, too, although its advanced scan uses data from the MB installation folder, itself. On the idea I had downloaded the MB uninstall file before MB had updated it to match the latest distribution file for MB, I looked over the MB website, found at least two download links, but both were identical, and neither worked. When something like this happens, it indicates MB probably is working in the background to interdict the uninstallation process, and the website is not designed to provide in-depth assistance. Sometime tomorrow, I'll chat with technical support, and see what they are prepared to offer.