One of the nice things about the latest Sophos SFOS v17.5 release is the Connect Client. Replacing the Cisco client was way overdue, but there are still a bug or two that need to be worked out.
The following was identified by Sophos Staff as a bug that should be sorted out in the next release. If you get a message from Sophos Connect Client “received NO_PROPOSAL_CHOSEN error notify” while trying to establish an IPSec connection, try doing the following to resolve the issue temporarily:
Make these two changes to the .tgb file.
1) Look for this line: Transforms = AES256-SHA2_256-GRP2 and replace it Transforms = AES256-SHA2_256-ECP256.
2) Look for this line: Transforms = TGBQM-ESP-AES256-SHA2_256-PFSGRP2-TUN-XF and replace it with Transforms = TGBQM-ESP-AES256-SHA2_256-PFSECP256-TUN-XF
Now import the modified .tgb file and try to connect again.
This solution was provided by Sophos Staff (much appreciated) and it worked for me so good luck!
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