Encontrou o problema.
Usado isto: link .
To avoid this issue, do not enable the "Run in logged-on user’s security context (user policy option)” Common option when configuring user GPP Scheduled Tasks items.
The security context under which the Scheduled Task will run once it has been deployed can be specified in the General settings tab when creating the User GPP Scheduled Task item:
User Configuration\Preferences\Control Panel Settings\Scheduled Tasks\New\"Scheduled Task (Windows Vista and later)"
General:
Security Options -> "When running the task, use the following user account:"
By default, this is set to: %LogonDomain%\%LogonUser%
This is where the security context under which the scheduled task will run should be configured.