Exchange Error: This e-mail address already exists in this organization


yet again Exchange is doing my head in:

I want to add a distribution group to our system with the email address, but every time I try, I get the message:

This e-mail address already exists in this organization.

ID no: c10312e7
Microsoft Active Directory - Exchange Extension

The object in question is a Public Folder called Jordans. The problem is that I have disabled Mail on the Public folders, propagated this down the tree , so as far as I know it shouldn't be holding on to this address.

When I perform a ldifde -f I get this result:

How do I make this folder release these addresses?


dn: CN=Jordans 15802784,CN=Microsoft Exchange System Objects,DC=MyCompany,DC=local
changetype: add
 CN=Public Folders,CN=Folder Hierarchies,CN=First Administrative Group,CN=Admin
 istrative Groups,CN=MyCompany,CN=Microsoft Exchange,CN=Services,CN=Configurat
cn: Jordans 15802784
displayName: Jordans
instanceType: 4
 CN=Jordans 15802784,CN=Microsoft Exchange System Objects,DC=MyCompany,DC=loca
objectClass: publicFolder
objectGUID:: vhN9EU5260C9J7y9L0DbOQ==
proxyAddresses: smtp:Jordans@MyCompany.local
proxyAddresses: X400:c=US;a= ;p=MyCompany;o=Exchange;s=Jordans;
name: Jordans 15802784
showInAdvancedViewOnly: TRUE
textEncodedORAddress: c=US;a= ;p=MyCompany;o=Exchange;s=Jordans;
uSNChanged: 199156
uSNCreated: 199131
whenChanged: 20050816130419.0Z
whenCreated: 20050816130409.0Z
msExchHideFromAddressLists: TRUE
mailNickname: Jordans
targetAddress: expf:JORDANS14A0AA7C46B75E4319DB0E8C2E1F65580000B2
deliveryMechanism: 0
msExchPFTreeType: 1
msExchALObjectVersion: 22
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Aslong as your Public Folder keeps the e-mail address (it is clearly shown in the SMTP proxy addresses which you provide in your question) you will keep getting the error.
Why don't you change te SMTP address(es) of your PF? Then the address you refer to will become available again. You can change them using the Exchange system manager.

You say "I disabled mail" - what exactly do you mean by that and how did you accomplish this?

are you able to see this PF in the MESO container when checking via adsiedit.msc

if yes then you can modify the attributes there.. you would find an attribute there which holds the smtp address and you can remove it from there.

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LetterpartAuthor Commented:
Thanks for your replies.


I can't change the address on the PF as I disabled the mail through ESM, All Tasks > Mail Disable


Yes I can see this PF in adsiedit.msc, but when I tried to remove the proxyaddresses in Properties, Select a property to view and then remove, then apply. When I next open it up in adsiedit, the values have returned.

CN= Jordans LDAP://RACKSERVER.mydomain.local/CN=Jordans,CN=Microsoft Exchange System Objects,DC=letterpart,DC=local

Thanks for your replies.


I can't change the address on the PF as I disabled the mail through ESM, All Tasks > Mail Disable


Yes I can see this PF in adsiedit.msc, but when I tried to remove the proxyaddresses in right hand click -  Properties - Select a property to view - remove - apply. When I next open it up in adsiedit, the values have returned.

are you able to change the proxy address of this public folder via adsieidt.msc?
LetterpartAuthor Commented:

No, I only had the option of remove and add. I could not change via adsieidt.msc. Although now trying it again, when I click remove it brings it up into the Edit Atribute window and I can now edit and then Add. <silly me>

Seconds before your'e last post I had removed all the proxys and then added a new SMTP: and this appeared to work. Next time I will remove then edit then add.

Just before I give you your well deserved points and thank you for your help, it is appreciated. Any idea why the PF still has an address assigned to it after I had disabled Mail on the PF's using ESM?


it could be a replication issue. what happens when you remove the address via adsiedit.msc and replicate the changes and dismount and mount the PF store. Do you still see an email address stamped on the PF?
LetterpartAuthor Commented:
If I remove the address via adsiedit it is fine. It is all the other folders which have had their mail disabled that are still showing proxyaddresses.

It doesn't really matter as I now know how to remove the address when I need to, but I would have thought that disabling mail would free up the emails, rather than just stopping you from emailing them. <sigh>
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