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paddy.christian@theblueschoolwells.co.uk: host aspmx.l.google.com[2607:f8b0:4023:1404::1b] said: 550-5.7.1 Emails can only be sent and received between accounts in theblueschool 550-5.7.1 wells.co.uk, theblueschool.somerset.sch.uk and other authorised 550 5.7.1 domains. (Blue School - email safeguarding policy) - gcdp z68-20020a25a14a000000b00d817e562d64si10443582ybh.40 - gsmtp (in reply to end of DATA command)