A Knowledge Based article has not been created yet, but Microsoft is warning users of Operations Manager that the installation of KB2775511(An enterprise hotfix rollup is available for Windows 7 SP1 and Windows Server) causes an issue that stops OpsMgr from working. Some issues exhibited by this problem show:

  1. No new events will be generated in the Operations Manager Event Log
  2. Errors in State Change Events will appear frequently
  3. Alerts will be generated during state change
  4. OpsMgr Managed Servers generating HeartBeat Failures and going into a greyed-out state
  5. Devices management by the OpsMgr servers are unmonitored

If the Hotfix has already been applied, Microsoft is suggesting that the removal of KB2775511 will fix the issue, and that anyone who has not installed the update already should refrain from doing so.

Microsoft's Warning: Notice: KB2775511 triggers Event 2115 in Operations Manager

In Does Microsoft have a Quality Problem?, the question has already been raised if Microsoft is doing due diligence to ensure that hotfixes, updates, and patches are being tested properly, particularly with their new rapid release schedule. Time will tell if they can get control of this.