Have you ever kicked off a deployment, walked away, then returned to find your newly imaged computer at the login screen? Of course you have. Have you ever logged in and then realized there are a bunch of things that didn’t happen during the deployment that were supposed to happen? The default error dialog timeout window is set to 15 minutes (it’s measured in seconds so 900 seconds). It would be nice to extend this timeout window so that the error dialog is displayed longer increasing your chances of seeing that the build failed, rather than delivering an incomplete device to an end user. All you need to do is set the task sequence variable (I recommend at the top of the task sequence) SMSTSErrorDialogTimeout = 86400
This will set it to 24 hours, more than likely you will notice the build failed within 24 hours so that any issues can be resolved.