I have an Acer WT 300 thin client that boots Windows CE. I purchased this device several years ago at an auction and need to reset the administration password so that I can alter the network configuration.
When I press F2 at the Terminal Connection Manger screen I'm prompted for a Terminal Settings password, which I do not have.
I think you need to determine what version of Windows CE the device is running, and find a way to recover or reinstall that. Look at the manual, there is not a 'hardware' password (like in the BIOS). It is all based in Windows CE.
If you can't reset the password maybe you can get into the registry and change the connection information. Here is some registry info for version 5.0, maybe some of is relevant for the older versions. Thin Client registry settings.