Browser windows shutting down (IE and Firefox), apparently at random. Task Manager shows a file called "58cnyw8m.exe", which seems to spawn the file iexplore.exe (possibly a worm?). When the file is active, Spybot, Malwarebytes, Ad-Aware etc fail to operate (Spy/Mal updated today, Ad-Aaware not so). I'm unsure of where this file came from. Desperately seeking solution.