This usually points to a resource conflict or an incompatible driver version (e.g., trying to run a 32-bit driver on a 64-bit Windows installation).

Navigate to the tab to change default baud rates, data bits, parity, and stop bits. Click on the Advanced button. Here you can:

These enhancements allow a driver to service interrupts much less frequently while sustaining high data rates, reducing context switching and CPU load.

This usually means Windows does not have the vendor-specific driver and only has a generic PNP ID. Download the latest drivers from the card manufacturer's website or the Oxford chipset reference site. Ports Not Appearing or Wrong COM Numbers

For embedded developers without OS support, here is a minimal driver skeleton: