Getting started with Microsoft 365/Exchange Online in 2021 is very easy and relatively cheap (I am paying 5 bucks a month for one mailbox and some extra stuff, like 1 TB of OneDrive storage).
Roughly speaking, here are the high level steps from beginning to end:
- Create your subscription
- Add a custom domain
- Verify the domain
- Add DNS entries for MX, Autodiscover, and SPF
- Create users
- License users
- Wait some minutes to see the mailbox in Exchange Online
- Add account in Outlook
After creating your tenant (easy to do, you can also work with a third party, instead of buying the subscription directly off of Microsoft), open https://admin.microsoft.com and select Azure AD. Unser Custom domain names, add the organization’s domain.
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You verify the domain by adding a TXT record to at the root of your domain. You could also verify by MX record, but usually the organization has some sort of functioning mail product, so in a migration scenario that is not an option.
@ means the root of your domain. In my case ajni.it
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Due to DNS Time To Live (TTL) and caching, this might take some time.
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Back to the Microsoft 365 Admin Center, under Settings > Domains select the newly added domain and then Continue setup. Add the 3 records to your DNS.
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Select Add your own DNS records. For mailing, Exchange Online and Exchange Online Protection records are needed.
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After correctly adding DNS records for Exchange Online, add a user in Azure Active Directory and assign the license. Very straightforward. Set usage location to your organization’s country. If you do not specify a usage location, licenses cannot be assigned to that user.
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Under License the license can be assigned.
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You could also choose to selectively assign certain products of the subscription. Either way one license will be burned.
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It takes some minutes for the mailbox to show up in Exchange Online after assigning the license.
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From now on, the account can be added in Outlook or accessed through Outlook on the Web https://outlook.office365.com