well, this appears to be a random issue related to windows updates. I have a Genius brand mouse, but on updating the OS -sometimes- it rejects the drivers
in favor of generic MS drivers. Running the normal driver
update results in nothing more than the standard "device is up to date" message, and Windows 7 will not recognize any downloaded drivers in the directory holding the manufacturer's files. My only solution has been to select "browse my computer" from the driver update options, then "let me pick" and uncheck "show compatible hardware" - viola, the manufacturer and actual drivers finally show up. Ignored the MS warning that they aren't compatible, it works. I've had to repeat the process a couple of times in the few months since I posted this. Hopefully it will help anybody else struggling with the same issues.