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22mahmoos@nhgs.calderdale.sch.uk: host ASPMX.L.GOOGLE.COM[2607:f8b0:400e:c03::1a] said: 550-5.7.1 Restrict Delivery: Your e-mail has been rejected, only internal e-mail 550-5.7.1 is allowed. Please contact the Administrator to enable your domain. 550 5.7.1 - gcdp i190-20020a6387c7000000b005645d9a89d6si22619243pge.554 - gsmtp (in reply to end of DATA command)