For some weeks now, some – but not all – emails I have been sending from Apple Mail are getting bounced.
In my bin, I can see a Google red traffic light icon.
And also the following:
554 5.7.1 Service unavailable; Sender address [xxxxx] blocked using uri.cal1.sophosxl.com
How can I stop this happening?
I would recommend you submit a sample of the bounced emails to the following URL .