On Windows, Maltego's (till version 4.1.15) default behavior was to save your license file in the ProgramData/Paterva folder on your machine.
This can cause issues if:
- The user running Maltego does not have write permissions for the ProgramData folder
- The ProgramData folder is shared between multiple machines
From version 4.1.15 on wards, the license is saved to User directory that should fix this issue.
If you experience issues saving your license file, or activating Maltego on Windows, then you should try saving the license key in the user directory instead.
From the first step in the activation wizard, check the "Advanced" checkbox and choose "User License"
Your license key will then be saved in your AppData folder instead.