Consider the following scenario:
You configure a maintenance window for a Microsoft System Center Configuration Manager 2007 Service Pack 2 (SP2) client.
You configure an advertisement to run on the client computer within the maintenance window.
The client computer starts or awakens from hibernation within the maintenance window.
In this scenario, the advertisement does not run within the maintenance window as scheduled.
The issue is caused by a timing issue between the service window manager and the execution manager. Both the service window manager and the execution manager start when the client computer wakes up within the maintenance window. In this situation, the service window manager posts a service window start event. Because of the timing issue, the execution manager is in its initialization process and misses the service window manager event. Therefore, the advertisement is not scheduled to run within the maintenance window.
To resolve this issue, install the hotfix package that is described in the following Microsoft Knowledge Base:
2516517 Task sequence does not run if it has lots of Install Software steps in System Center Configuration Manager 2007 SP2
To work around this issue, use one of following methods:
Remove the maintenance window for the client.
Start or wake up the client computer before the maintenance window starts.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.