VPN not working on Gateway Max 2

[Cheezy2]

Telstra sent me a replacement modem because my Gateway Max TG799vac had to be restarted once a week to keep it working. The new Gateway Max 2 TG800vac is working fine except I can no longer use my VPN to my office.

The VPN connects ok, but I cannot connect over it, Remote access fails.

If I teather my PC or Laptop to my phone it all works fine but not using my new modem on the NBN.

I have rung Telstra and get the standard run arround and no help. Told to contact my office IT person, not much use as that is me. Just a bunch of robots on the phone reading a script and not willing to listen or help. 

[ForensicsGuru]

Hmmm... Interesting... My 799vac works perfectly OK with Palo Alto Global Protect VPN and there was report that it does not work wit CISCO, however TG800vac does (https://crowdsupport.telstra.com.au/t5/Modems-Hardware/Telstra-Gateway-Max-drops-VPN-after-20-second...). Can you report VPN system you are using for the reference?

[Cheezy2]

I am using Shrewsoft free VPN client and a cisco.pcf. Had to use Slysoft as Cisco client won't work with windows 10.

This works fine with my old Gateway Max modem which was replaced as it is having some issues.

I just reconnected the old modem for a test and the VPN works fine over it.

[ForensicsGuru]

Bummer, we have just decommissioned our old, sort of archaic CISCO device few days ago, so I do not have any way of testing... But it sounds weird to me...