We are running ArcMap Desktop 10.5.1, and connect to enterprise geodatabases through SQL Server ArcGIS Server 10.7. Up until recently we were all able to work in the geodatabases over Cisco VPN. On May 7th, only two out of four of us can no longer open the geodatabase connections, nor create a new geodatabase connection to ArcGIS Server. I see no Windows Update taken place on that date, or the previous date, and can find no reason for any change in the two laptops that can no longer connect. Anyone else had this or similar problem?
Ok, I think that this would be an easy install / test to see if it is an ArcGIS client issue or other issue.
You mention that it worked till May 6th. Besides Windows updates, you may need to reach out to your IT dept. to see what (if any) other network, database, VPN rules changed.
Where there any ArcGIS patches applied to the Server / Geodatabase?
What are the errors that you are receiving in the ArcMap when connecting?
I would download it from Microsoft here: https://docs.microsoft.com/en-us/sql/ssms/download-sql-server-management-studio-ssms?view=sql-server...
Once installed, try to make a connection to the SQL Server instance.