I have very stupidly removed the admin account on a WS-C3750G-24WS-S25's WLC. Is there any way of accessing the device without having to reset it to factory default settings? It's a production device and I could do without having to re-configure the entire box. Cheers.
If the admin account is removed and you do not have any other account with admin privileges, there is no other option but to reset to factory defaults. Here is more information on managing user accounts.
Sorry, I thought I would throw this reference doc as well :(
Password Recovery for the WLCM
When the password to login to the WLCM is lost, the only way to get into the WLCM is to reset the WLCM back to default settings. This also means that the entire configuration on the WLCM is reset and has to be configured from scratch.
Refer to Reset the WLCM to Default Settings for information on how to reset the WLCM to factory defaults.