A client is running ODBC 4 on their server and the license is intermittently expiring and then goes back into evaluation mode.

I can reactivate by logging on the console as administrator and using the Automatic Activation function, however the serial number changes each time. 

Firstly- any ideas why the license is expirying in the first place, and how can this be prevented?  We have already tried to deactivate, uninstall and then reinstall.  Secondly - does each re-activation count towards the total activations available or when I reactivate is the license count unaffected even though the serial number changes?

Thanks in advance.

Your client's FlexODBC license key has been corrupted. The license key is actually hidden in NKJUDB7E.ocx when the registration system was first used and is found in the C:\WINDOWS\system32 folder. Please rename it to .bad, reinstall FlexODBC (don't reboot) and manually reactivate the desktop. If the original Software ID is unchanged, the registration system will recognize the Software ID and re-active it without decrementing a seat count.

You will need to ensure that all users, services, the Internet Guest Account (IUSR_<machine_name>), ASP.NET Machine Account (ASPNET) and INTERACTIVE accounts have read and write permissions to NKJUDB7E.ocx in your System32 directory. It may be a hidden, system file.