using custom domain in office 365 1

[AzizKamal]

I need to know about user restriction in office 365. I would explain my query through an example.

Suppose an organization has its own domain (say myorg1.com) and hosting plan. The hosting plan allows the creation of 100 email addresses. After two years, the organization purchased office 365 business essentials plan that allows the creation of maximum 300 users through office 365 admin center dashboard. The organization purchased the office 365 business essentials plan for 300 users. Office 365 provides onmicrosoft.com domain by default. However, it also allows adding a custom domain you already own to office 365. Suppose the organization adds its own domain myorg1.com in office 365 and makes it the default domain. In this scenario, when the administrator will create new users and select myorg1.com in the User name's domain dropdown, how many users can the administrator create at maximum? Will the administrator be restricted to create only 100 users and not allowed to use the full quota of 300 users?

 

[AzizKamal]

I found the following link on office.com website:

https://support.office.com/en-us/ar...fice-365-6383f56d-3d09-4dcb-9b41-b5f5a5efd611

According to the above link:

When you change your email to Office 365, by updating your domain's MX record in the next step, ALL email sent to that domain will start coming to Office 365. If other people use your domain for email, you must set up Office 365 mailboxes for each of those people. Otherwise they'll lose any email sent to them at your domain when you switch email for the domain over to Office 365.

From this information, what I infer is when a custom domain is used in office 365, emails first go to the domain hosting plan of myorg1.com and then they are moved to office 365 hosting. Hence, email address should be defined in myorg1.com hosting plan. Consequently, myorg1.com will only be able to add maximum 100 users in office 365 with @myorg1.com user names. Administrator may add other custom domains to use the full quota of 300 users. In other case, the administrator may assign onmicrosoft.com domain for the remaining quota.

 

[strongm]

You infer wrong. You are switching your mailhost away from the current host to an Office 365 mailhost. The issue that paragraph is highlighting is that if you do not create Office 365 mailboxes for each mailbox currently existing on the current host then those users will no longer receive email since it will all be going to the Office 365 host, where they don't have a mailbox (the email migration wizard does not create mailboxes on Office 365, unless the source server is Exchange)

 

[AzizKamal]

Thanks strongm.

It means that I can create up to 300 email addresses of my domain on office 365 (for the mentioned plan) even if my current host allows only 100 email addresses. Right?. Furthermore, I will have to migrate all 100 emails to office 365. I cannot do say 75 email addresses on office 365 and 25 email addresses on current host?

 

[strongm]

Correct