I did some further investigation and tried to manually download the updater xml file. It clearly gets distorted with a Web policy in place, hence the error.
So I think this is a Sophos XG issue and reported it there.
But why is PatchMyPC not using SSL for fetching? Downloading the updater file from https://patchmypc.com/freeupdater/definitions/definitions.xml works fine in both cases.
So I think this is a Sophos XG issue and reported it there.
But why is PatchMyPC not using SSL for fetching? Downloading the updater file from https://patchmypc.com/freeupdater/definitions/definitions.xml works fine in both cases.