Migrate Office 365 inbox to another inbox within the same tenant.

[kidrock_1977]

Hi,

 

Got a bit a issue which I wanted to get some advice on. First some background information. I work in a school as a IT Tech and in previous years the AD Accounts (as well as email address) have taken the form of first letter of first name and first letter of second name "@ourschool.org.uk". Example if there was a teacher called John Smith his AD account would be [email protected]. I have been asked to recreate all the staff accounts (for a variety of reasons!) in the format of [email protected]. Example John Smith would now be [email protected]. Thats fine as I have created a nice powershell script to recreate the AD Accounts. My question is, is there a way I can migrate their old mailbox (i.e. [email protected]) to the new one (i.e. [email protected]) with some sort of powershell script? Or does someone know of a good third party tool? Let me know if that makes sense.

 

Thanks!

[chaplic]

Dont do this! Unless you really, really, really want to start afresh with permissions, content and so on. Just change the existing accounts.

 

I'm assuming you are just projecting your AD accounts to O365, so in AD simply change your userprincipalname to the new desired entry, and add all desired aliases to the proxyAddresses AD field in the format

 

SMTP:[email protected]

smtp:[email protected].

 

Check your client impact as sometimes outlook can be huffy with a new UPN, but worse-case it will want a profile rebuild but may just work.

[kidrock_1977]

Hi Chaplic,

 

I Managed to find a post relating to exporting and importing .pst files using the compliance centre in office 365.

 

Thanks

[chaplic]

I think what you're doing is bonkers, but all-the-best.

 

If you are determined to do this, quest-on-demand can migrate contents of mailboxes in the same tenant, doing a compliance centre export is painfully slow (I suspect most tenant to tenant tools would do inter-tenant moves but not tested).

[elsiegee40]

Serious question… isn’t it more sensible to create aliases (or whatever they’re called in O365) for all the existing accounts and then new starters get the new style email?

 

So JohnSmith@ is an alias for JS@ and mail is automagically redirected into the JS@ mailbox.

 

That way the old email address is still live for those that don’t know it’s changed… logins created by staff for third party systems that you have no control of don’t have to be changed… and it’s far less risky.

 

All new staff automatically get the new style email address as they’re starting from scratch.

[Boredguy]

We are redoing all the usernames within our trust to be in the same format (since we currently have 5 different variations on staff and student usernames, and is phase 1 before we merge the tenancies), so is similar to what you are doing.

 

Our steps are

- Update AD Username to match new format (checking across the trust to make sure we've got unique username)

- Update AD e-Mail field to new address

- Set the proxyAddress field so that SMTP: is the new address, and smtp: is their old address as an alias for the next 3-6 months (when it then gets removed)

- Update the Office 365 Principle Username so that the sign-in address matches the new primary e-mail address and not the old one that is now an alias

Set-MsolUserPrincipalName -UserPrincipalName [email protected] -NewUserPrincipalName [email protected]

 

Any new starters will automatically get the new format

 

 

The steps above is basically what we do when-ever a member of staff requests to change their name, so the process works nicely.

Edited January 26, 2022 by Boredguy

[MatthewL]

That is what I would do, recreating user accounts good luck with that and the hassle.