Office 365 Send as cPanel Mailserver Domain

I have been given another E-Mail domain used by another company I am a part of however they do not use Office 365.
They will not change their mailserver but will allow DNS changes as long as it does not effect their own mailflow. They are simply setup with a cPanel hosting account for a mailserver.

I want to know if the following is possible to setup:

My current E-Mail address in Office 365:
My other E-Mail address hosted externally:

The other E-Mail address does not support active sync and only supports POP3 and IMAP. The goal is to not require 2 accounts to be setup on all my devices. I can make all E-Mails redirect from the address to my own address but I need to be able to send out as me@ as well.

So my main question is:
Can I:
1. Setup an initial txt record on the new domain to validate the ownership of the domain to O365.
2. Then add the me@ address as another account of in O365.
3. Then setup full rights to me@ for so that I can use my O365 account to send out as

There could therefore be no mx record changes to the other domain.
Would I then add an spf record for the other domain to allow E-Mails to be sent from O365 as well as their mailserver?

Will any of that work? If not how could I set this up?
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Vasil Michev (MVP)Commented:
1) Yes
2) yes
3) Sending As or on Behalf of another user will require you to pay for another license. You can use a Distribution group or shared mailbox for the to avoid having to pay for additional licenses. Simply adding the address as alias to your own account will not do the trick as you can only send as the Primary alias in Exchange. There are other workarounds as well, but DG/shared mailbox should be best for you.

No need to adjust the SPF as mails sent from this account will be coming from *
IT101Author Commented:
Thanks vasilcho, I will give this a try today.
I also stumbled upon the "connected accounts" section in O365 options that allows you to add IMAP/POP accounts. It works great except for the fact that it adds "on behalf of" to all the sent items which therefore does not solve the issue.
Hopefully the above is the work around though.
I will post back as soon as I try it later today.
Vasil Michev (MVP)Commented:
Connected account will also work, but the mail will still be delivered to the 'original' mailbox first, and then fetched to the Office 365 account. In other words, make sure to keep the mailbox active in your current hosting configuration.

Here are some links that might help you:

Shared mailboxes:


If you choose a shared mailbox, make sure to configure the forwarding settings or create a rule to get the messages delivered to your own mailbox. You can add yourself as delegate directly from the creation dialog.

If you choose a DG, simply add yourself as a member. Once you have created the DG, double-click on the name and navigate to group delegation to grant the permissions.

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IT101Author Commented:
Yeah thanks,
I am trying it as a shared mailbox but when I alter the FROM field in outlook to read I am getting immediate undeliverable receipts.
Wondering if it takes a while to propagate the shared mailbox settings and if I should just be more patient.

I have setup the shared mailbox and given myself full and send as perms so it shouldn't be a perms issue.

Only other part that might be holding it up is that I did not fully complete the domain setup...
I simply did the first step to validate the domain but did not add mx records and users as I do not intend to do this. If you think this could be the issue I could probably add the mx records at high values, finish the wizard and then remove them once I get the "Active" flag on the domain in O365.

For additional info the undeliverable is simply:

Your message did not reach some or all of the intended recipients.

      Subject:      test
      Sent:      9/10/2013 7:34 AM

The following recipient(s) cannot be reached:

      'My Name' on 9/10/2013 7:34 AM
            This message could not be sent. Try sending the message again later, or contact your network administrator.  Error is [0x80070005-00000000-00000000].
Vasil Michev (MVP)Commented:
First of all, test from OWA to make sure the permissions are applied correctly. Make sure to select the shared mailbox directly from the Global Address Book and not from any cached entry. The same goes for Outlook.

MX has no impact here. Also the NDR you are getting is a bit strange, if you were lacking the permissions should simply say that
IT101Author Commented:
Yeah that's definitely it... but its a bit of a problem....

So if I use outlook and click FROM -> Select Other Email Address... FROM... and choose the shared mailbox from Global Address List it works just as you said.

After doing so it adds a new entry to the from drop down to represent the shared mailbox address. But when I select it here and send I get the bounce again.

I have noticed that in outlook the shared mailbox has not hit my "Offline Global Address List" yet (its only in the "Global Address List")... Could this be effecting its lookup process somehow? If so, how can I force the offline address book to be updated?
Vasil Michev (MVP)Commented:
It takes a while for the OAB to synchronize with the GAL, you can force this by going to Send/Receive -> Send/Receive Groups -> Download Address Book -> clear the checkbox to download only changes.

Also delete any old stored entries from the name cache for this address, simply start typing the name and when the entry pops up, press the little X on the right side.
IT101Author Commented:
Just to make it fun I am currently getting update errors when trying to update the OAB as you noted above.

When trying to diagnose the issue I get to Step 6, point 8 of the following link:
At this point the username and password I add to display the xml page in IE does not authenticate (I am using my main office 365 account with the for username and its password for password.

The link I get for the OAB.xml from step 6 is in format:<STRING>/OAB.xml

Any ideas?
IT101Author Commented:
Oh also just to note down the actual error in outlook when trying to update the OAB:
Task 'email address' reported error (0x80190194): 'The operation failed.'

Open in new window

Vasil Michev (MVP)Commented:
This happens for all mailboxes or? There was an issue on MS side affecting OAB the past few days, it should be resolved now but who knows...
IT101Author Commented:
Very well could have still been effecting me.
As of this morning though the OAB updates correctly and therefore all tests are now working. (Can select from drop down list in from button after initial selection).
Thanks for all your help vasilcho
IT101Author Commented:
I went with using a shared mailbox and it worked a treat. Thanks again
IT101Author Commented:
As a final sidenote, any way of sending as that shared mailbox email address from IOS and Android?
Vasil Michev (MVP)Commented:
Not sure, last time I checked they did not support this. You can always use the browser on the device to open OWA and send from there.
IT101Author Commented:
Yeah that's what I thought too.
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