I would have the network staff at the client location investigate their network and its settings. It sounds like there may be a connectivity issue, caused by any number of issues.Phil Brammer | http://www.ssistalk.com | Twitter: http://twitter.com/PhilBrammer
Proposed As Answer bySQLUSASaturday, November 14, 2009 6:46 PM
This is a generic error saying your client has trouble connecting your server.
This error can be cause of myriad of reasons it could be your NIC card Or your anti virus software or sometime Active Directory stuff.
Are you using Windows Authentication or SQL authentication? If you are using Windows authentication then try using SQL authentication and see it works (at least it will eliminate active directory stuff)