Hi Chuck,

Toontrack Solo requires no serial, so I’m guessing you are referring to EZ Lite asking to be authorized while used in Toontrack Solo.

The authorization process is shown in detail in this video:
http://www.toontrack.com/support/?prod=EZdrummer%20and%20EZX%20expansions&issue=Authorization&os=Other&seq=Other&ID=13

Here is also a step by step instruction:
• launch software in Toontrack solo (latest version found via the Free Downloads section) or your host on the same machine/configuration as you intend to authorize use on
• upon launch, a screen comes up saying ‘…not authorized…’
• please copy the Computer ID displayed in this screen
• log in to your original account account (where your product is registered)
• go to My Products and select the correct product in the menu on your right
• paste Computer ID, enter a short description (anything, i.e My Computer), and hit ‘Authorize’
• copy the authorization code and paste it back into the screen in the software.

Done and done! Please note that the computer ID will be different from computer to computer, so you will need to authorize twice since the authorization code is unique for each computer ID