The User Account Is Unknown – Task Scheduler

When trying to run a scheduled task as a specified user, you may get this error:

Task Scheduler

Task Scheduler cannot create the task. The user account is unknown,
the password is incorrect, or the user account does not have
permission to create this task.

This error is different the the following error which means that the username is wrong:

Task Scheduler

An error has occurred for task TaskName. Error message: The
specified account name is not valid.

The user account is unknown error means that the username is valid, but one of the following things is a problem:

• The password is incorrect;
• the user doesn’t have permission to run the task;
• there’s a bug whereby you have to be logged in as the user you’re trying to run the task as.