We have this weird problem what stops any internet access via the browser, but applications such as Outlook / Teams / To Do continue to work, as well as pinging domain names (purely to test internet connection).
I recently figured out that Sophos is the cause, I went into the effected laptop and disabled the settings via 'Admin Sign In'. This has now rectified the issue so I turned them all back on, but the browser is now working again (even though they're back on).
This seems to be happening to the odd few laptops in our business, but now appears to be happening often and making it's way through the business.
Any one else got this issue? We're unsure of the fix in all honesty, seems to fix itself then go again after a week or so.
P.s. Google works, and it's searches but that is it!
Unusual for sure.
Thanks for reaching out to the Sophos Community Forum.
Could you let me know if any network firewalls or other appliances are also performing filtering on the network connections? Does disabling the "Network Threat Protection" component from the local policy override allow browsers to work as expected when this issue occurs?
If you can also let me know if the issue is specific to a certain model of device, that will help. Let me know what version is shown under the "About" section of Sophos Endpoint.
Thanks for getting back to me.
Just checked with the team and nothing else is performing filtering.
When I did the override test, I switch it all off which wasn't the best test in hindsight, however this will happen again so I will only disable Network Threat Protection. However, I do believe this one would be the cause.
The laptop models in question are -
Dell Latitude 3520 (11th Gen Intel Core i5)
Sophos info -
Core Agent - 2022.2.1.9
Sophos Intercept X - 2022.1.1.22
Checking internally, it looks like there is an open development investigation related to this issue. I suggest gathering the following logs while the issue is present. Once you have the logs, I suggest opening a support case so that your case can be associated with the ongoing development ticket.
- Procmon Log- Wireshark Log- SDU Log
Once you have the support case opened, you are welcome to send me a PM with the case number.