Posted 11 July 2012 - 12:44 PM
I have had the same problem with my HP6510b, and I solved it this way.
First I bought a new replacement battery, calibrated it and charge it. So now it is working as it should.
Spare part number from HP is 443885-001.
Then I installed the latest Ethernet drivers and tested with different combinations of network configurations.
If I turn off the wireless, the uninstalling the Ethernet controller disappears.
Only if you run both the Ethernet and the wireless, the Ethernet controller is uninstalled when you disconnect the charger.
So probably this is an normal power saving feature. If you already got the wireless running, somebody at HP must have thought that you don't need the network cable.
So try different configurations. If you run on battery power, the Ethernet controller is not uninstalled - if you have turned off the wireless.
Good luck / Bengt