Question 1

Install fails or shows Code 10/28/43?

Accepted Answer

Uninstall any existing USB-to-serial driver in Device Manager (enable View > Show hidden devices), reboot, then run the RadioShack installer as administrator before plugging in the cable. If it still fails, update the driver manually by browsing to the extracted driver folder.

Question 2

Device not detected or COM4 missing?

Accepted Answer

Try another USB port and cable. Check Device Manager for Unknown Device or Ports (COM & LPT). If the cable appears without a COM number, open Properties > Port Settings > Advanced and assign COM4 or another free port.

Question 3

Driver/version conflicts?

Accepted Answer

Remove conflicting Prolific/FTDI drivers if the adapter uses an older chipset. Keep only one driver version installed, reboot, and verify under Ports. Avoid Windows Update if the vendor installer fails.

RadioShack USB to Serial Cable (COM4) Driver