The above post began as a question.  While typing what didn't work, I developed the answer.
Hardware:  Dell Laptop with Dell 375 Bluetooth adapter running Windows 8Problem:  After Microsoft Windows 8 update, all Bluetooth devices stopped working.  Moreover, they could no longer be discovered to pair them.  Device manager showed everything working fine.Failed Repair Attempts:- Uninstall all Bluetooth components in Device manager and Scan for hardware changes.- Uninstall Dell 375 software in Programs & Features (WIDCOMM Bluetooth Software) in order to reinstall (R296919).  The installation was promptly blocked by the Program Compatibility Assistant.- With the Dell software uninstalled, I thought perhaps that it was no longer needed, and thus the Microsoft software would work.  I again uninstalled all Bluetooth components in Device manager and Scan for hardware changes.  Still could not pair.- Checked in services and Bluetooth services were running.What worked:- Run GPEdit and go to Computer Configuration/Administrative Templates/Windows Components/Application Compatibility/- Enable the following:  Remove Program Compatibility Property Page  Turn off Application Compatibility Engine  Turn off Program Compatibility Assistant- Run services.msc and stop Bluetooth processes- Extract R296919 into a directory- on R296919.exe and select Run as Administrator - For me, the installation failed the first time.  I then repeated it, and it installed fine, but demanded a reboot, which I did. - At this point, I was able to pair Bluetooth devices again. - Open Device Manager and navigate to Bluetooth/Dell Wireless 375 Bluetooth Module.  and select Properties.  Click on the Power Management tab and uncheck "Allow the computer to turn off device to save power" and press OK.  If you don't perform this step, you will have all manner of problems with Bluetooth devices including mice and keyboards. - Reverse the GPEdit changes back to Not Configured. - Reboot   How to avoid the problem: Microsoft has a driver update that states it is for the Dell 375 Bluetooth adapter.  on the the update and choose Hide update.  Microsoft has been having quite a few Black Tuesdays lately, and this update is just another example. 
Dell 375 Bluetooth no longer works after Windows 8 Update, R296919 blocked by 
Program Compatibility Assistant - How to fix