Solution
To change your serial number, you'll need to deactivate and then reactivate your software using the new serial number.
1. Deactivate your software, following the steps in the KB article:
Deactivate or Remove License for NI2. Reactivate your software by following the
NI Activation Wizard Walk-Through and using your new, updated, or correct serial number.
The updated serial number will appear in NI License Manager, which can be opened by navigating to
Start » Programs » National Instruments » NI License Manager.
NI License Manager 4.0 and higher:
NI License Manager 3.7 and lower: