Minimum OS Permissions required to create named pipe (WCF)

No special permissions are required for a locally logged on user to set up the service end of a WCF service using the netNamedPipe binding.

However, you do need to worry about whether the clients can find and connect to the service. There are two aspects to this:

1. The clients must be running in a security context which is not established by a network logon (such as impersonation of a remote user in a web application). This is because WCF denies access to any logon which is a member of the NETWORK USERS group.
2. If you are running on Vista or Windows7, the service exe will need to be running with the privilege SeCreateGlobalPrivilege if you want the service to be accessible to clients running outside the logged on user's session. This is because the WCF service needs to publish the pipe name to a shared memory object to enable clients to find it: if the WCF service stack can create this shared memory object in the Global namespace (visible to all logon sessions), it will. But if it does not have the necessary privileges, it creates the shared memory object in the Local namespace (visible only within the same logon session). Deploying the WCF service as a Windows service is the only easy way to get it running with this privilege and thus visible to clients outside its session.

More details here if you are interested.