RFC Error: Too many attempts to log on

What causes this issue?

The user is locked in the backend system because of too many failed
logon attempts.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Run the user management transaction SU01 and unlock the user.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.