Prolific USB Error Code 39

The Prolific USB Error Code 39 is very common with the Prolific serial equipment. This mainly occurs as the driver had not been installed correctly. Prolific makes good equipment however for some odd reason the serial adapter has a tendency to show a driver error. This error tends to occur with the PL2303 serial adapter.

Prolific USB Error Code 39

Error Code 39 in relation to a Prolific USB device indicates a problem with the driver software. Specifically, it means that the driver for the device is either missing or corrupted in the Windows operating system. This error prevents the device from functioning correctly.

To fix Error Code 39, you can try the following steps:

1. Update or Reinstall the Driver: Go to Device Manager, find your Prolific USB device, right-click and choose “Update driver” or “Uninstall device.” If you uninstall, restart your computer, and the system should automatically reinstall the driver. If not, update the driver using the latest version provided by Prolific.
2. Check for Windows Updates: Sometimes, Windows updates include fixes for driver-related issues. Make sure your operating system is up-to-date.
3. Manually Install the Driver: If automatic methods fail, you can try manually installing the driver. Download the latest driver software from the Prolific website, then use Device Manager to manually update the driver by selecting the downloaded file.
4. Check for Hardware Issues: If none of the software solutions work, there might be a problem with the USB port or the device itself. Try connecting the Prolific device to a different USB port or a different computer to rule out hardware issues. Also check the hardware as the new drivers don’t work on certain older chips. See also the article on Prolific USB to Serial Comm Port.

Always make sure to back up important data before making significant changes to your system, such as reinstalling drivers or updating operating system components.

Expert Options

The first step if it is an error 39 is to uninstall the driver in your Control Panel and re-install the driver again. This fixes the problem. Should the above not work then also see the following:

The Prolific USB Error Code 39 can be a frustrating issue, but there are steps you can take to fix it:

1. Check BIOS Settings: Ensure USB ports are enabled in your computer’s BIOS/CMOS settings.
2. Run System File Checker (SFC): Use this tool to repair or replace damaged system files, which might be causing the error.
3. Run Check Disk: Identify and fix hard drive errors by running a disk check.
4. Refresh USB Stack: Uninstall all USB Serial Controllers from Device Manager and restart your system. This can refresh the USB system and resolve driver conflicts.
5. Registry Edit (Advanced): If you’re comfortable with advanced settings, edit the registry by changing the ‘Enabled’ value in the specified registry path. Exercise caution, as incorrect changes can harm your system.
6. Roll Back Driver: If a previous driver version was working fine, revert to that version for a potential solution.

Always remember to restart your PC after making changes. If the problem persists, consider reaching out to your system administrator or the software vendor for further assistance. Be cautious while editing the registry, as incorrect modifications can seriously affect your system. Lastly also see the USB shows please insert a device error on here.

See: Prolific USB to serial driver