I am having the same problem. Now configured 4 Units - all the same result (so I am making the same mistake?)
Connecting 100% from IPcop to IPcop, cannot convert from IPcop to Endian due to this issue.
Using ADSL's with "All traffic" routed to "Red-interface" - can PING both side from both sides - Web-interface also working 100%
Configuration is easy and straight forward:
1) Menu -> VPN -> IPsec
2) Global settings -> Enable (activate all debug for testing)
3) Connection status and control -with "Use a pre-shared key:" and as per per IPcop
4) Firewall -> VPN Firewall turned Off
I must be missing something
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I will hugely appreciate any assisting/guidance and have TeamViewer to double check my configuration.
Thank you in advance
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Phillip