Hello there!
This encryption key is indeed stored in a file on the Lansweeper server, making it impossible for anyone to decrypt your credentials unless the Lansweeper server itself is already compromised. Additionally, you would need to "find out" how to reverse the encryption.
We would recommend visiting our trust center for more information regarding security and compliance: https://www.lansweeper.com/trust/
Should you still have questions about security and compliance after visiting our trust center, don't hesitate to contact our security team directly, as they are best suited to answer your questions.
Our security team can be contacted via email: security@lansweeper.com