Ouch! A windows server security patch of the .NET Framework can break SharePoint. The following link goes into details about the security patch its effect.
Click link for more details about patch and fix
Microsoft does not have a fix for SharePoint. I recently had a customer apply the patch and then removed the patch. This doesn’t work but worth a try. The only option for recover is to restore the windows image from a previous backup. It a good practice to always back up the windows image before applying patches.
Here is my suggestion
- Windows server image backup of all the servers and all SharePoint databases.
- Apply patches
- Run SharePoint Configuration Wizard on each server. This is often overlook by window server engineers because they don’t understand that patches really don’t get applied to SharePoint until the wizard is run
- Test and verify SharePoint.
Hopefully patches work and SharePoint is running. If not, the backups can get you back to your happy places.