R2LIC is Rainlendar’s proprietary commercial license for the Rainlendar Pro edition (commonly called "R2 License" or "R2LIC"). It grants a single user the right to run Rainlendar Pro on up to two computers owned or used by that user (typically a desktop and a laptop). It includes commercial use rights and access to Pro-only features and support.
Sync with Google Calendar, Office 365, Outlook.com, and CalDAV. rainlendar license r2lic
If your license is very old (e.g., from version 1), it may not work with Rainlendar 2.x versions unless upgraded. from version 1)