If you are using Mozilla Firefox through a Sophos UTM then you need to go through the following steps. Mozilla Firefox is the only browser which we can not roll out the certificate which is required for Web Browsing.
Go to the following URL in Mozilla Firefox (http://passthrough.fw-notify.net/cacert.pem).
Once you go to this site, you should get the following prompt.
Make sure you tick both the “Trust this CA to identify websites.” and “Trust this CA to identify email users.”
Click OK and your web browsing will return back to normal.
If you have any issues, please email our helpdesk.