Windows firewall blocks communication between the client and server.

On the server:

1. Go to: Start, Control Panel, Windows Firewall
2. Turn Windows Firewall off for Domain Networks, Private Networks, Public Networks or add a Port Exception:

To add a port exception to the Windows Firewall:

1. Log into the computer as an Administrator, Click on Advanced settings
2. Right click on Inbound Rules, New Rule, Port, Next.
3. With the dot in TCP (default), with the dot in Specific Local Ports: Enter the value 2638 (Network) or 1433 (Premier), click Next.
4. With the dot in Allow the Connection, click Next.
5. Check all boxes for Domain, Private and Public, click Next.
6. Enter a value in the Name: field, click Finish.
7. Repeat same to add Outbound Rule.

On the client:

1. Go to: Start, Control Panel, Windows Firewall
2. Turn Windows firewall off for Domain Networks, Private Networks, Public Networks or add a Port Exception:

To add a port exception to the Windows Firewall:

1. Log into the computer as an Administrator, Click on Advanced settings
2. Right click on Inbound Rules, New Rule, Port, Next.
3. With the dot in TCP (default), with the dot in Specific Local Ports: Enter the value 2638 (Network) or 1433 (Premier), click Next.
4. With the dot in Allow the Connection, click Next.
5. Check all boxes for Domain, Private and Public, click Next.
6. Enter a value in the Name: field, click Finish.
7. Repeat same to add Outbound Rule.

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