Schduled task failed to run - TI 2009 mystery

I have scheduler set to run two back up tasks TI 2009 - make backup image to two different locations - both have run successfully until today. The one set for 11:00am today failed with this message -

I don't run this PC with any password logins and although UAC is set to "on" I have already completed a number of successful backups to this location using this scheduled task. Anyone any idea why today should be different?

The one set for yesterday completed without incident. I have run todays from the scheduler under "run task now" and it has completed -incremental and validated without incident?

 

Hello Faust,

Thank you for choosing Acronis Disk Backup Software.

It is clear from error message that our program unable to get access to your account to schedule task.
There are several workarounds which may help you to overcome this issue:

First of all, please make sure you use the latest build, which is available on our web site at here. To get access to updates you should first register Acronis software here.

1. Specify credentials for Windows Administrator account in task
2. Recreate the task itself

Please also notice that you can find detailed information on Acronis True Image in the respective User's Guide.

If the issue still persists, please create Acronis Report and Windows System Information as it is described in Acronis Help Post.

And send us the log with the error as described below:

- Start Acronis True Image Home;
- Select Tools -> Show log;
- Choose the log entry which contains errors;
- Click on the diskette icon, choose the location (folder) and save there;
- Send us the log.

Then submit a request for technical support. Attach all the collected files and information to your request along with the step-by-step description of the actions taken before the problem appears and the link to this thread. To expedite the resolution we recommend you to use our Live Chat service after that. We will do our best to investigate the problem and provide you with a solution.

Thank you.
--
Alexander Nikolsky