Sharepoint Troubleshooting: Value cannot be null. Parameter Name: Farm
When running the “stsadm-o updatefarmcredentials” command we encounter the error "Value cannot be null. Parameter Name: Farm”.
In this case, we use the same account for both SQL and SharePoint.
After updating the correct password for the SQL services in services.msc, we can now run the command without issue.
Note: If you find a different solution, please report it as a comment to this post. This will be useful to the SharePoint Community. Be sure to double-verify it: undo your solution and verify that the problem comes back, then redo it and verify that the problem goes away.