Found in

• 102.2.0 ESR

Affected versions

• Firefox 102.2.0 ESR
• Firefox 104.0b9
• Firefox 105.0a1

Affected platforms

• Windows 7

Preconditions

• Make sure the following prefs are set:
  • app.update.log=true
  • app.update.background.loglevel=debug
  • app.update.background.scheduling.enabled=true
• Make sure the When Firefox/Nightly is not running option is checked inside about:preferences
• A task scheduler for the Background Update Agent can be found inside Task Scheduler

Steps to reproduce

1. Add the policies.json file (see attachment) to distribution folder inside Firefox install location
2. Launch Firefox and check that the following policy is active in about:policies
3. See task scheduler Library

Expected result

• The message inside the console reflects the fact that the task is deleted
• The Background Update task scheduler is removed

Actual result

• The following message is displayed inside the browser console:
  BackgroundUpdate: maybeScheduleBackgroundUpdateTask: exiting after uncaught exception in maybeScheduleBackgroundUpdateTask!
  Exception { name: "NS_ERROR_FAILURE", message: "Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIWinTaskSchedulerService.deleteTask]", result: 2147500037, filename: "resource://gre/modules/TaskSchedulerWinImpl.jsm", lineNumber: 60, columnNumber: 0, data: null, stack: "deleteTask@resource://gre/modules/TaskSchedulerWinImpl.jsm:60:16\ndeleteTask@resource://gre/modules/TaskScheduler.jsm:145:18\nmaybeScheduleBackgroundUpdateTask@resource://gre/modules/BackgroundUpdate.jsm:469:31\n", location: XPCWrappedNative_NoHelper }
• The Background Update task scheduler is not removed

Regression range

• Will see for a regression if there is one.

Additional notes

• The issue can be seen in the following attachment
• The issue reproduces on my Windows 7 system, while on another Windows 7 system the task is deleted and the error is not present
• Tried with clean environment (deleted all profiles, folders in Program Data/App Data, registries) on my machine but the error persisted and the task was not deleted

I have managed to reproduce this issue on the latest Release v108.0.2 and on builds as old as Release v90.0 on my Win7 system, however, I suspect it might be related to the fact that the Task Scheduler sometimes freezes or crashes. When attempting to reproduce on even older builds, the Task Scheduler no longer launched properly so the investigation could not be continued.

The Task Scheduler showed the error: "MMC has detected an error in a snap-in and will unload it. Exception has been thrown by the target of invocation. Exception type: System.Reflection.TargetInvocationException". I imagine this is not related to the installation and use of Firefox, but my system will be reinstalled and the issue will be retested.

I have retried these steps in the same system, but with a freshly installed Windows 7: The issue could no longer be reproduced as the as no error is displayed in the console regarding the background update and the task is removed.

I think it is safe to assume that this behavior can only be observed on a faulty system.

Closing based on Comment 2