The April 2019 Patch Tuesday updates from Microsoft are causing conflicts with several Anti-Virus products including ones from Avast and Sophos.
The sign that your computer is suffering from this issue is that it will hang at the Windows 7 welcome screen indefinitely after a reboot.
The fix is to boot into Safe Mode, disable the Anti-Virus service, boot into normal mode and remove the updates.
This update has been blocked for clients on one of our Managed Services plans and was not scheduled to be installed until this Saturday.
For help resolving this issue, please contact our office at (630) 595-5200 or email firstname.lastname@example.org.