laptop issues with authiticating to domain over wireless

I just ran into this yesterday, customer has a desktop and a laptop. the laptop doesn't get started up very often as it is used for board room presentations. she had changed her password last week on her desktop. all good. she fired up the laptop, let it connect to the wireless and tried to log in. she couldn't. she then typed in her old password and was able to get connected to the network though she didn't have her mapped drives and desktop. She did have access to internet but when I manually mapped a drive (install folder for example), it asked me to type in a username and password so I knew there was still an issue with authentication. I logged in as the administrator and manually mapped drives without any issues.

I took the laptop and connected it with a network cable, logged in as the user with the new password and all was good. disconnected it, took it back into the board room and logged her back in again with her credentials and all is good.

The environment is Windows 2008 domain server, laptop is running Windows 8 Pro.

So what might be the issue here?