Answer: 

Use the following steps to resolve the connectivity problem:

1. Try to manually ping the server to check its existence in the network
2. Be sure that the firewall of both Server and Node are turned off
3. If you are using Quick Heal firewall then check the following:
   1. Right Click on Quick Heal Firewall Icon on Task Bar
   2. Click on Setting
   3. Click LAN Setting under Firewall
   4. Check all the three check boxes
   5. Use Apply button
   6. Use Ok button

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