Problem Retrieving Available Updates Error

When running an update on a server, under Server > Updates menu, and you get the error: There was a problem retrieving the available updates. There was a problem accessing the external server. Please check that your pbx has access to the internet. (500 Connection failed: connect. Connection timed out)
Or you may see the error: ! There was a problem contacting the Update Server

Instructions for troubleshooting:
Assuming that your server does have access to the internet:
Start a Packet Capture on Switchvox (go to Server > Advanced Debugging > Start Debugging Sessions > Packet Capture) and capture all packets, not only SIP.
Then, go to Server > Updates. The top part of the update page shows the Subscription Expiration. The subscription server is contacted at updates.switchvox.com:443. 

In the packet capture, verify that the Switchvox server is sending requests to the Updates Server's IP Address using port TCP 443. Check for replies from the Update Server IP Address. If there are no replies back from the Subscription server:

1. Verify that the firewall on the Switchvox network, allows ICMP from the Subscription server to the PBX (see List of  Digium Switchvox Servers). When loading the Updates page, Switchvox sends an ICMP packet to subscriptions.switchvox.com first, to make sure that the system is still has valid support. The PBX tries to ping (using ICMP) the Subscription server and only proceeds if it gets a response. If there is no response to the ICMP packet, you will see: 'Error Contacting Update Server'.

2. Check to see if the DNS Addresses contain the loopback address: 127.0.0.1 If so, delete from the Server > IP Configuration > DNS Addresses field.

NOTE: Saving this page will restart the server and drop any active calls.

1. Check your DNS to see if the Switchvox server can properly resolve updates.switchvox.com to the correct IP Address in the Packet Capture. You can also check this by pinging "updates.switchvox.com", from a command line prompt, on a workstation. If the hostname cannot be resolved, then your DNS is not working properly. You can add a Google server IP address (8.8.8.8) to your Switchvox under Server > IP Configuration > DNS Addresses. (add 8.8.8.8). NOTE: Saving this page will restart the server and drop any active calls, so you may want to do this after business hours.

2. It is possible that port TCP 443 is not open on your network. Therefore, the PBX cannot retrieve updates from Updates server.  Verify that the firewall allows traffic on port 443 TCP.

3. The Subscription server may be down (see List of Switchvox Servers). Digium Support can verify if that is the case with a Support Lead or IT department.