Problem: Users received “Cannot connect to the configuration database” error when trying to access SharePoint sites!
Reason: SQL Server services were stopped during a patch installation. (In another case, SQL Server service stopped due to disk space issue!).
Start SQL Server Service!
- Go to SQL Server Configuration Manager
- Right click on “SQL Server (MSSQLSERVER)” Service which is in “Stopped” State, and Start it.
You can do the same with the Services console. Go to Run >> Services.msc >> start the MSSQLServer Service!
But wait! There could be some other reasons for “Cannot connect to the configuration database” or “Unable to connect to database. Check database connection information and make sure the database server is running” error in SharePoint, such as:
- Network connectivity issues between SharePoint Web/App Servers and Database Server. Make sure your SharePoint servers are able to communicate with SQL Server by pinging/NSLookup. Also make sure no firewall rules are blocking your connections. Verify Named Pipes is ON.
- The SharePoint service account used in App Pool doesn’t has enough access to SQL Server! Make sure your AppPool account has: Security Administrator & Database Creator rights on SQL Server. It also occurs when your service account password expires or account is locked.
- Try IISReset. Simply a Server Reboot also works sometimes!
- SharePoint database(s) may be in Offline mode, bring them Online from database properties!