An error in my registry

I have a error code 2506 in my Event viewer from the service “Server”

The value is RestiictNullSessAcess in the server’s Registry key Lanmanserver\Parameters
this key in invalid so I will be glad if anyone out there can tell me what to do with this problem.

Write to me on this mail brn@birkeroedkom.dk if you can help me.

Brian Nielsen