Without running the cache builder after installing new REs, Reason may crash, fail to load, or show error messages during startup.

If you lose internet access or if the authorization servers go offline, your purchased REs become unresponsive. Furthermore, if you are using a legacy version of Reason (e.g., Reason 10 on Windows 7) that no longer receives updates, you cannot authorize newer REs.

It ensures that all extensions load simultaneously without crashing the DAW.

: For users running R2R releases, this tool is considered essential. Without rebuilding the RE cache after a fresh installation or update, Reason typically encounters errors during the initial plugin scan. Performance Optimization