Makes of this adapter. Microsoft has NEVER supplied the drivers so your method of using the Microsoft device manager should not work.
Try this. Use the drivers from it's maker.
Also, if you had the make and model I might have the link to the driver or if it's that other obscure brand I own I have the driver for that one. -> In closing there is no generic driver.
Bob
Very frustrating. I have an old Kenwood shortwave radio that provides computer connectivity via RS232. However, my computer only has USB. Try as I might, I cannot get the USB-Serial adapter cable drivers to install correctly in XP. I have even tried additional drivers for other makes of adapter cable with the same result. There is always an exclamation point next to the USB-to-Serial Bridge and Human Interface Device entries in Device Manager and no new COM port is apparently created/opened. Trying to update or reinstall the drivers from there only gives some useless message akin to "can't find information on hardware" or "can't find software." Until this link is functional, I cannot determine if the RS232 communication from the radio is working. Maybe a separate RS232 card is the answer. I know that compared to other problems in this forum, mine is trivial. But hey, I'm compulsive and would sure like to play with the radio on the computer. Thanks in advance for any help you can offer.

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