MS Exchange error 5.1.4

I want to have two contact records in my Active Directory to have the same SMTP email addresses.  I can set them up and use the Global Address List in Outlook to select either of the entries and all works well.  But when I type in the raw email address I get the 5.1.4 error (Exchange can't resolve the display name of the address)

OK, I understand how the problem can originate but it seems to me that there must be a way around it.

For example:
I have two contact records in my Active Directory at  They share a common SMTP address to an account (say: acct@AOL.COM).  These two people appear in my organizations Global Address Book as contacts and when I select one or the other the email gets sent with no problem.  But when I type in acct@AOL.COM in the To: message area, Exchange returns this 5.1.4 message and doesn't send the message.

How can I tell exchange to ignore the ambiguity and send it anyway?
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MartoneConnect With a Mentor Commented:
but it's one account, two people in exchange can share an email address too, in a distribution list.  
munichpostmanConnect With a Mentor Commented:
You cannot force Exchange to ignore the ambiquity. If you wish two contacts to share the same smtp address, why not create the two contacts in ad with seperate email addresses but then add them to a distribution group and give the group one smtp address?
andyfitzAuthor Commented:
That would work if the two contacts had separate email accounts somewhere.  The problem is they don't.

for example:
    Mary Smith          =
    John Jones           =

I want both Mary and John to show up in my Global Address List for those who have access to our Exchange server so they can be selected by their individual name by a user who may know them.

I want another user who may not have access to the Global Address List but uses a pop account to our server to be able to type in and have it sent without a 5.1.4 error.
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MartoneConnect With a Mentor Commented:
In exchange, email addresses cannot repeat.  no two users can have the same email address.  

what you can do thoough is have one email address, ie, and give both users access to that account.  but stil one of those users will have a different email address, ie, but will have full access to

make sense?
andyfitzAuthor Commented:
Makes sense for Users but not for Contacts.  

In Outlook I can set up several contacts with the same email address and all is well.  What is the problem with Exchange Contacts?  In Active Directory a Contact entry does not give the person logon authority (there is no sAMaccount name and no Exchange mailbox); it should be just an informational entry.  If Exchange can't resolve an email address because there are two of them in AD - so what? The entry should validate as at least being known to the organization. It would just use the typed in address instead of a display name - that is what happens when you type in an email address that is not in AD.

MartoneConnect With a Mentor Commented:
that is a limitation in exchange.

here may be a workaround:
create a contact with the email address you need
create two user accounts with the appropriate names
under the Exchange General tab for these two accounts, click on the Delivery Options button
then select to forward it to the contact account

does that work for you?
andyfitzAuthor Commented:
no good.

AD Contact records do not have delivery options.  The Contact names we are adding are not members of our domain and therefore we do not want to add them as User accounts - just have them appear in our Global Address List.

This is getting to sound more and more like a bad design feature of Exchange - or are we so unique that no one has ever run into this before?
MartoneConnect With a Mentor Commented:
not the AD contact records, but the actual user account has Delivery Options.  basically you would just forward email from the two User Accounts to the single Contact

why does it matter that they aren't members of your domain, it can just be a dummy account, that is used to forward email to a contact

you can have them appear in the GAL, but they can't have the same email address.  

if you think about it though, in all of the internet there is no two people that have the same email address, which is probably why exchange doesn't allow it either
andyfitzAuthor Commented:
"if you think about it though, in all of the internet there is no two people that have the same email address, which is probably why exchange doesn't allow it either"  - Huh?  My wife and I share an email address.
andyfitzAuthor Commented:
The real issue here is for OUTGOING email.  That is why these people are set up as Contacts.  They do not have an email address within my organization and we don't want to give them one.  They are added to our AD with their outside email address as a convenience to other members of my organization.

I can't set them up with different email addresses because they don't have different email addresses.  A distribution list would be a way to solve the problem if they had separate addresses.

I am pretty frustrated by what to me should be a simple situation.  For OUTGOING email just send the email.  If it can't resolve a mailbox for incoming email that is a different issue.

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