A trial expired warning message is displayed if you have upgraded to a new major version or downloaded an upgrade from the Redgate website. This is so that the licensing server can check that your license is entitled to the upgrade.
To move back into licensed mode, you'll need to activate your serial key. You can do this one of two ways depending on the product:
On the Help menu, select Manage my license > Refresh license
On the Help menu, select Enter serial number
Related article: Prompted to 'INSTALL FREE TRIAL' when upgrading SQL Prompt
Sometimes, the licensing server fails to communicate with the tool and can remain stuck in trial mode. If this happens, follow these troubleshooting steps:
Log out and then log back in, to see if your licensed serial key is recognized.
If after logging in again the license still reads: 'X days left on your SQL XXXX trial' and below you have the options to Continue trial, Activate or Buy now, please log a ticket with support and attach your service logs from C:\ProgramData\Red Gate\Shared Client\Log.