Cant connect to Server using SSMS on my desktop SQL SERVER 2008 R2
When attempting to connect to the default instance of sqlserver on our local server from SSMS on my desktop I'm receiving the following error. 


  A network-related or instance-specific error occurred while
  establishing a connection to SQL Server. The server was not found or
  was not accessible. Verify that the instance name is correct and that
  SQL Server is configured to allow remote connections. (provider: Named
  Pipes Provider, error: 40 - Could not open a connection to SQL Server)
  (Microsoft SQL Server, Error: 5)



I've verified that the server is set for remote connections inside
the instance - properties - connections.
I've verified that TCP\IP and Named Pipes are enabled under
Configuration Manager - sql server network configuration - protocols
for MSSQLSERVER
I've verified that the browser service is running and that the sql
server service is running.
I've verified that the 1433 port is opened in the windows firewall.


I'm not sure what else to check.  I'm using the correct servername. If I attempt to connect using IP address I get the following error.


  A network-related or instance-specific error occurred while
  establishing a connection to SQL Server. The server was not found or
  was not accessible. Verify that the instance name is correct and that
  SQL Server is configured to allow remote connections. (provider: Named
  Pipes Provider, error: 40 - Could not open a connection to SQL Server)
  (Microsoft SQL Server, Error: 5)


Any help would be appreciated.
Try to run telnet from your local machine and use the following from command line 

telnet [servername/ip] port

ex:> telnet sql01 1433

This will at least verify that you can hit the server on the specified port. As well your local machine could have a firewall enabled or perhaps a 3rd party application that could be blocking your access?

You can consider it a successful test if after pressing ENTER your command window goes blank. (It has successfully started the telnet session - type some random characters to go back to your normal DOS prompt).

A failure would look like this:


  Connecting To sql01...Could not open connection to the host, on port
  1433: Connect failed