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Re: "User Unknown" errors related to DNS issues?
On Mon, 13 Dec 2004, Jim Popovitch wrote: > > Hi all, > > I see a periodic problem with some email servers that report "User > Unknown" for valid users. The most recognizable problematic host is > hotmail.com, but there usually are others mixed in (today's additional > problematic hosts included msn.com, verizon.net, and incentre.net). > > Do others see this same issue? > Hi Jim. I don't think your problem is dns related. We had problems with many hotmail/msn accounts returning user unknown for valid users. We tried solving it by resending all email and ignore 550 errors/bounces up to 50 times (several emails were delivered even after 40 550 bounces). Unfortunately hotmail complained about it after short time because it generated very many bounces. They suggested signing up for bondedsender.com. Temporary resolved the problem by still ignoring 550 but up to 15 times and retry in a slower sequence. We might sign up for bondedsender though.. seems like an okay idea. Joergen Hovland ENK