I renamed user on server from "administrator" to "serveradmin" because of recent worm. For few days everything work great but now recuring windows tasks fails to execute with status:
Logon failure: unknown user name or bad password (0x8007052E)
Also, it is not possible to create new tasks:
Task Scheduler service is not available or the folder does not exist. Verify that the service is running and that the folder exists.
Also, it is not possible to modify settings of existing tasks. It states that Author of tasks is [servername]\Administrator.