Why is XP COM port complaining it cant load the driver (Error31)

[philwai]

Uninstallation of all NI software and reinstallation of the V1.6 upgrade results in COM3 and COM4 visible in XP Device Manager at the usual addresses and sharing IRQ 7 with an ! over them.

The first port complains "This device is not working properly because Windows cannot load the drivers required for this device. (Code 31)". The second port complains "Windows cannot load the device driver for this hardware because a previous instance of the device driver is still in memory. (Code 38)"

Using the NI software to test the ports the software and hardware are ticked off but COM3 and COM4 are not shown ... help!!!

[JoshuaP]

Try right-clicking on both devices in the Windows Device Manager and select uninstall. Then open Measurment and Automation Explorer (MAX) and go-to Tools->NI-Serial-> Recover Unused Serial Ports. Hopefully, this will get your system back to a safe state. Then, just reboot your computer.

I hope this helps out.

-JoshuaP