I can't make out the name of the company in that picture.
Searching for "TQ49 MIDI" doesn't yield much, although it does turn up
an old post in another forum which mentions that "in the device manager it comes up as a 'PHECDA USB/Midi device'."
Searching for "PHECDA USB MIDI device driver" yields a number of hits, some with downloads available, although I can't tell if they're safe-- several of the results look like they just took the search term and created a bogus page (i.e., the text doesn't seem to have any bearing on a TQ49 MIDI keyboard). And the only two that don't look totally bogus look suspicious for other reasons (i.e., their download links appear to be for downloading a "Driver Toolkit Installer" rather than the claimed "PHECDA MIDI Driver Installer"). I'd steer well clear of those places.
Apparently the keyboard is so old that it doesn't work without the proper driver, and it's possible that the company is no longer in existence, or was perhaps absorbed by another company. If you can identify a company name on the keyboard, that might help with turning up better search results, otherwise it might be less trouble to just buy a new inexpensive 49-key controller to replace the TQ49.
On the other hand, the following Microsoft Community thread might help:
http://answers.microsoft.com/en-us/...7/042c82cb-bbd6-4ced-a247-0063a6c16d7f?auth=1