mimecast.co.za has no AAAA records.
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Microsoft
Domain verification
MS=ms28051725
161709df418b4d9bac6bce87d4795998
_5gqdgv14mh00qfhwmn1euksl1az0dxq
jjhmqtge87uajs8lf984et20h8
t3x95sfgq2c7hwhpfncjskmf6xgvrj1f
Zone apex
Start of authority
Email
Serial
1773872643
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5m
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5m
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7d
Negative cache TTL
1d