SharePoint 2010 Error Product / patch installation or server upgrade required.
We got this error on Production, though the windows updates on all web front end and app servers were same. The cumulative updates for SharePoint were same on all boxes.
This tends to happen if there is a mismatch of windows updates or cumulative updates for SharePoint all web front end and application servers.
Automatically install windows updates was turned off.
Agreed a downtime
Run this in Powershell
PSConfig.exe -cmd upgrade -inplace b2b -wait
Somehow this didn’t work and failed had to run this forcefully.
PSConfig.exe -cmd upgrade -inplace b2b –force
This fixed the issue for me. If this had failed, I would have relied on upgrade.log file and ULS logs to understand why the product config failed