Internet Explorer cannot display the webpage
  
   Most likely causes:
You are not connected to the Internet.
The website is encountering problems.
There might be a typing error in the address.
 
“Diagnose connection problems”

this usually means that a firewall is runing somewhere between the two computer and is blocking 40681 …the remote firewaqll might be blocking your connection”

In sharepoint server , change the setting of windows firewall to open the port through Windows Firewall.  In Windows Windows Firewall, select “Excptions”, and “Add POrt”.