Some of the TCP Ports needed for communication to SQL Server through a Firewall. You need to add these ports and services to the firewall exception list.
Error Message 8: An error has occurred while establishing a connection to the server. When connecting to SQL Server 2005, this failure may be caused by the fact that under the default settings SQL Server does not allow remote connections. (Provider: TCP Provider, error: 0-A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.)
Cause: Due to connection blocked by Windows firewall.
Troubleshoot: To resolve this, take follow steps:
- Enable SqlBrowser
- Add SqlSERVR.exe into Firewall exception list
- Add SqlBROWSER.exe into Firewall exception list
- Add Tcp port to Firewall exception list. (eg, Name-1433:TCP, Value-1433:TCP:*:Enabled:Tcp 1433).
- If you are using some third party firewall then contact the vendor for more detail.
- For more detail please see the related links.