Default behavior for failed deployments in ConfigMgr is for the error box to stick around for 15 minutes before rebooting. That's plenty of time if you have nothing better to do than watch progress bars and wait for failures. But what if you have work to do and you need the error to stick around a bit longer?
If you want the default timer to change, simply create the following Task Sequence Variable and stick it at the top of your deployment:
SMSTSErrorDialogTimeout = 86400 (24 hours)
Some things to note about this:
- Timer is measured in seconds
- Default is 15 minutes (900 seconds) if you're good with that, you don't need to set this variable in your Task Sequence at all
- WinPE will automatically reboot after 72 hours. While you could technically set this to infinity, WinPE is going to disregard the setting. However, if you're in setup or better yet state restore, you'll be able to keep the dialogue box as long as you want (or until Windows Update reboots the computer )