3.8.19.1 (Latest stable release for most Z-TEK models) Release Date: January 19, 2018
If the device appears under "Other Devices," it means the driver didn't install. Try a different USB port or use the Hardware and Devices Troubleshooter .
This often occurs with older Prolific chips on Windows 11. To fix this, you may need to manually roll back to an older driver version (like 3.2.0.0) that still supports legacy hardware. Z-tek Usb To Serial Comm Port Driver Free Download
You should see "Z-TEK USB-to-Serial Comm Port (COMX)" without any yellow exclamation marks. Troubleshooting Common Issues
Once the installation wizard finishes, connect your Z-tek adapter to a USB port. Windows should automatically assign it a COM port number . Verify in Device Manager: Right-click the Start button and select Device Manager . Expand the Ports (COM & LPT) section. To fix this, you may need to manually
Often identified by USB\VID_067B&PID_2303 (Prolific) or USB\VID_1A86&PID_7523 (CH340). Microsoft Update Catalog
Supported on both x86 (32-bit) and AMD64 (64-bit) systems. Windows should automatically assign it a COM port number
Obtain the latest version (v3.8.19.1 or newer) from the Microsoft Update Catalog or the manufacturer's provided link.
If your software requires a specific port (e.g., COM1), you can change this in Device Manager > Port Settings > Advanced . Remember to restart your computer for the change to take full effect. Driver Specifications
Right-click the .exe installer and select Run as Administrator . If you are installing from a .zip file, extract all files first.