use new chipset), your unit has the older chip version. Please check your UC232A serial number on the back of the unit (see picture) If the 3rd digit is less or equal to '9' (note letter such as A,B,C, etc. Fixes for Prolific devices: windows-10/0a4f8e48-7135-4434-9d10-349c9ce87fcf Older Driver ver 3.6.81.359: You might be using an old UC232A 'chipset' version that is not compatible with Windows 8 and later OS. Recommended to use ATEN UC232A USB to Serial For Windows 10+ make sure it uses the PL2303HXD chip.

In Windows 8 Device Manager the yellow warning symbol will show for converters that used to work in Windows 7 but are too old to work now: In Windows 8 a newer name brand converter will work fine: The DNC Server software itself works fine on Windows 8. So if your USB to Serial converter worked in Windows 7 and doesn't work in Windows 8, it is probably because you have an older or no-name brand converter that does not have the latest version of chip in it. Surfing on the back side of the wave.Note on Windows 8-10: Windows 8-10 is NOT supported for older versions of prolific chips. I got Active Sync awake and forced it onto port 7 Bluetooth USB (where it was). When I plugged in the Zoom Bluetooth USB dongle, all the ports installed again. I found that there was a collision on port 6, so I deleted all the BT ports ' on Bluetooth RFCOMM from TOSHIBA'. (Although I don't recall this particular error message.) Eventually they'll collide with a number that was assigned to a different device, and not work. When I use USB serial adapters if I'm not careful about plugging them back into the same USB port that I used them in the first time, they get assigned to different COM port numbers.

Hinermad wrote:It's sort of a brute force approach, but if you get desperate you might try going into your Hardware Manager and deleting all your COM ports (unless you have dedicated serial ports too - don't try to delete those).

Prolific usb to serial comm port 7