Why does an SQL Server instance become unavailable on the network?

1

I have an occasional issue with connecting my VB.net database program to a server on the network using connection strings. Usually it works just fine, but every so often the customer(s) complain that the program won't connect. Not because I have changed the connection string or anything - which I haven't - but because of some unspecified or automatic change or update possibly to the customer's server's firewall, anti-virus etc.

Usually we fiddle with administrator levels, permissions etc. until connection is re-achieved. Is there some way we can 'future-proof' the connection between program and SQL Server so it doesn't fall over when there's a Windows update or etc?

Customers SQL Server version is 10.50.

Any pointers or suggestions welcome. Thank you.

2

You need to stop automatic updates to the server and firewall. Updates to those components need to be controlled, regression tested and scheduled for off-hours deployment.

3

To know more how to fix the issue:

SQL Server instance become unavailable on the network.

follow this one Enable Remote Connection on SQL Server 2008 Express - Linglom.com