I am unable to connect to my local instance of SQL Server 2008 Express using SQL Server Management Studio.

I believe the problem is related to a change I made to the connection protocols. Before the error occurred, I had Shared Memory enabled and Named Pipes and TCP/IP disabled. I then enabled both Named Pipes and TCP/IP, and this is when I started experiencing the problem.

When I try to connect to the server with SSMS (with either my SQL server sysadmin login or with windows authentication), I get the following error message:

A connection was successfully established with the server, but then an error occurred during the login process. (provider: Named Pipes Provider, error: 0 - No process is on the other end of the pipe.) (Microsoft SQL Server, Error: 233)

Why is it returning a Named Pipes error? Why would it not just use Shared Memory, as this has a higher priority order in the list of connection protocols? It seems like it is not listening on Shared Memory for some reason?

When I set Named Pipes to enabled and try to connect, I get the same error message.

My windows account is does not have administrator priviliges on my computer - perhaps this is making a difference in some way (as some of the discussions in this post about an "SuperSocketNetLib\Lpc" registry key seems to suggest).