This happened to me after I installed the Broadcom BT stack. To get rid of the NDIS error when I went to uncheck the USB to PC option I did the following:
1. Remove the Axim X51V from the cradle.
2. Edit the X51V registry. I used PHM Registry Editor Version 0.7 or any registry editor.
3. Look for the registry key:
HKEY_LOCAL_MACHINE\Comm\RNDISFN1\Parms\TcpIp
Change
EnableDHCP=1
to
EnableDHCP=0
4. Quit the registry editor using Tools > Exit. I did not soft reset the X51V.
5. After making the above registry change, dock the X51V. I waited more than 30 minutes and still no error. Before the registry change, the error appeared between 1 to 3 minutes after docking the X51V.
This allowed me to uncheck it without the error.
I also made two other tweaks that were mentioned. They can be found by following these links.
http://www.aximsite.com/boards/showp...&postcount=637
http://www.aximsite.com/boards/showp...&postcount=650
Hope this helps.
Michael