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Make sure that you are connected to the internet
Close any NVivo projects you have open
Click the File tab, Product Info, Manage License and then Deactivate License
Confirm deactivation, and close NVivo
Restart NVivo
Most likely you are still logged in with the profile you were logged in with before deactivition.
If the license you want to use is in an account you have access to under this profile, continue below to activate.
If the license you want to use belongs to an account under another profile, log out of myNVivo, start NVivo again and log in with the profile you want to use.
In the dropdown, select a the second license and click Activate. (If you have logged in with a new profile there may not be a choice of accounts—in this case just click Activate.)
It may close and restart NVIVO and you may need to log in again
The software is now activated