First published on TechNet on Apr 25, 2006

We've seen a few cases where uninstalling a SQL 2000 SP4 instance may cause loss of connectivity to other SQL instances.  This may happen when you uninstall an application that uses SQL/MSDE, when you manually uninstall a SQL instance, etc.

So, you uninstalled a SQL 2000 SP4 instance, rebooted, and now you can no longer use Companyweb (Sharepoint), the SBS Monitoring feature is not working, and if you have ISA 2004, you notice that you have lost all connectivity to the server (i.e. the server is in lockdown mode).

These are just a few of the problems that you might have and all caused by a single checkbox and is removed by accident when uninstalling a SQL 2000 SP4 instance.

We are talking about the Shared Memory protocol no longer enabled on this server for clients to use when connecting to any of the other MSDE/WMSDE instances.

To fix this:

Click Start -> Run

Type CLICONFG and press OK

Once the SQL Server Client Network Utility opens up, put a check in “ Enable shared memory protocol

Click OK to save the changes and then manually reboot the server.

Thanks to Damian Leibaschoff for this tip (a KB is forthcoming, but we wanted to make people aware of this).