BigSur with Sophos Endpoint - OneDrive for Business files don't download

So, i have narrowed this down to the Threat Protection Device policy and the 3 options under Real-time Scanning - Internet. If any of the the 3 options are enabled then OneDrive stops downloading.
The 3 options are "Scan downloads in progress", "Block access to malicious websites" and Detect low-reputaion files".

Presumably this is down to the service(s) that these options enable on the client end and seemingly aren't disabled when doing the admin login and disabling all options (as i did to test initially).

With one of these options enabled it shows in the Services section of the Self help tool 3 services "Sophos SXL", "Sophos Web Intelligence" and "SophosWebNetworkExtension". These aren't present with all the Real-time Scanning options off.
They are also all showing green so presumably should be working.

It is worth noting that everything else seems fine, i can access the web in Chrome and Safari and even my onedrive via the web accessing the same files i'm testing synced in the client.

My test machine is a fresh install of Big Sur, not an upgrade.

Thank you for reporting this. 

I will direct this to the development team to look at further. 

Can we get an SDU from the machine and a tcpdump during sync where it succeeds and one where it doesn't.

have you rebooted the machine since upgrade and allowed the web control proxy permissions?

Hi Richard, yes i have. I have also removed and reinstalled Sophos client just to be sure nothing was missed. As i was testing the policy changes to see which fixed it i rebooted at each change as well. This issue was seen on at least 4 machines so doesn't seem to be a specific machine related problem.

I will get this to you asap. I'm travelling today.

Please be on the lookout for v10.0.3. The update is rolling out this week and we'd be keen to know if any of the fixes made improve this for you.

Hi David, looks like things are worse with v10.0.3 as i now can't get OneDrive to download files even with the changes i made to get it working previously (3 options in Threat Protection Policy in my update above).
When the download fails i get "Error code -16".

With Sophos client uninstalled OneDrive works fine.

I have uninstalled, rebooted, installed, rebooted, updated, rebooted and made sure all the permissions are given for full disk access.
I'll do some testing with policy changes and feed back.

I have now found the options i need to disable in the Threat Protection Device Policy.
I have to leave the original 3 options under Real-time Scanning - Internet ("Scan downloads in progress", "Block access to malicious websites" and Detect low-reputaion files") disabled but now also "Protect network traffic" under Runtime Protection. After this and a reboot, OneDrive works fine.
If any of these options are enabled and a reboot done OneDrive sits trying to download files but eventually fails, usually ith error code 16.