550 bad hello

  1. K

    Do you have 2 reasons for 550 rejection?

    Often you might have seen 550 rejections or 550 bad hello. Behind all the activity, there is only one smart user called spammers. Yes! You would have seen a set of people working to build a building on a construction site. All those people are men who work for a long time. Likewise, spammers use...
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