One of our Windows VPS customers received the following error while connecting to the MSSQL server.
Error message
A connection was successfully established with the server, but then an error occurred during the login process.(provider: TCP Provider, error: 0 - An established connection was aborted by the software in your host machine.) Microsoft SQL Server, error: 10053)
Upon checking the error message in the event logs, we came to know that the connection on the MSSQL server was already made, and new connections were being rejected. To fix connection restrictions, we set the user connection limit to unlimited as follows.
1. Open the command prompt with Administrator privileges and issue the following commands.
sqlcmd
exec sp_configure 'user connections', 0
reconfigure
2. After issuing the above commands, restart MSSQL service.