Exchange 5.5 - server rejects some emails...

[groovin]

Recently a user is having a problem where some emails from certain people do not get through. Some emails are bounced back with a 'The recipient name is not recognized' NDR, but most just disappear into oblivion. Some emails from these peopel do get through. Most people that email this user get through... its just a hand ful that dont.

has anyone seen anything like this? ive already ruled out any filtering/anti spam progs that are running.... and once again this problem just started happening... no changes made to the server at all.

thanks

 

[Abzstrak]

if its only rejecting email from certain people, maybe its due to something specific to their DNS? does it always tell those people to F off or just sometimes? maybe its reverse DNS lookups?

 

[groovin]

just sometimes... some of their mail gets through... some doesnt.

can you explain how it could be a reverse DNS problem?

thanks

 

[Abzstrak]

sometimes some people email FROM certain people gets through? or sometimes some emails TO certain people get through?

If memory serves, exchange 5.5 always performs a reverse dns lookup on all emails that some in, and if they fail the lookup an error is generated. I think that you have to use regedit to change this behavior, you can find the key to change on technet somewhere.... so I guess it could be that.

the more I think about it the more I think its not this..... u could try it anyway.

 

[Abzstrak]

also U miight want to run a soft repair on the DS

 

[groovin]

sorry, brains been a bit racked lately... too much radiation from the servers i guess...

what i meant was...

we have a mailbox bob@domain.com on our exchange 5.5 server... bob usually gets all his email except from jack@someplace.com, sue@someotherplace.com, and ebay. Sometimes, he gets his emails from jack, sue and ebay, but most of the time those emails either never get through and an NDR is generated, or they dont get through and no NDR bounce back is created.

thats it in a nutshell. not trying to insult your intelligence by the dumbed down explanation, but just wanted to make the problem clear since my own communication skills suck! =)

Now, if it was a reverse DNS problem as you described, wouldnt all users on this exchange server have the same problems with jack, sue, and ebay? my mailbox is mike@domain.com and i can get all my emails from jack and sue.

thanks again

 

[Abzstrak]

ok, so its just the one user experiencing this problem?

why not just delete and recreate his account and see if it helps?

and yea, don't think its reverse DNS I misunderstood the issue.

 

[groovin]

what effect would deleting/creating his account have on his current email and other settings?

 

[Abzstrak]

I'd just use exmerge to get his data out to PST, then delete his account, and probably reboot the sucker... I'd run a soft repair on the DS and then make him a new account, set it up the same, then use exmerge to reimport all his emails. Depending on the size of his mailbox mainly, it shouldn't take too terribly long, maybe 20-30 minutes to do this.

 

[groovin]

thanks for your help! i'll try what you suggested.