The following articles were included in our Exchange Messaging Outlook (EMO) newsletter published on August 28, 2025.
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Today's Highlights »
- Switch from Microsoft 365 Personal to Business Standard
- Microsoft is limiting the use of onmicrosoft.com addresses
- Outlook stopped accessing Gmail
Switch from Microsoft 365 Personal to Business Standard
A user wanted to know how to switch from Microsoft 365 personal to a business standard subscription.
Switching the license is normally easy in Windows: in File > Account in any office app, click Change license and enter the new address. Restart Office and check for updates if you are changing versions. (On Mac, you need to use the license removal tool.)
The user had a problem: he was using a custom domain address for his personal Microsoft account and moved his email hosting to Microsoft 365 business. When an address is used on both the business and personal side, logging in can be a problem.
The solution is to add an outlook.com alias to the account and remove the address that is now on the business side.
Add an alias at https://account.live.com/names/manage. If the address is used to sign into Windows, Microsoft will automatically update it within a day or two and may ask for your password.
It was surprisingly painless when I changed the addresses three accounts. I tried it on husband’s account first, just in case there were issues.
Microsoft is limiting the use of onmicrosoft.com addresses
Beginning October 15, 2025, Microsoft will start limiting how many outbound addresses onmicrosoft.com addresses can send. Finally! Too many spammers use the accounts for spam and phishing.
Microsoft will start with trial accounts in October, blocking them from sending more than 100 messages a day from the tenant’s onmicrosoft.com addresses. Trial accounts will need to add a custom domain address to their account to send more than 100 messages.
While this may not stop spammers from abusing Microsoft 365 tenants, they won’t be able to use the tenant address in hopes of tricking users into thinking it’s official mail from Microsoft.
Accounts with paid mailboxes will have from between November 2025 and June 2026 to update addresses, including for shared bookings, to update default SMTP addresses for all sending accounts. The exact date depends on the number of licenses purchased in the tenant.
Users with Microsoft 365 business software subscriptions but no mailboxes (or Teams accounts) do not need to add a custom domain to their tenant as they do not send mail.
More information: Limiting onmicrosoft Domain Usage for Sending Emails
Outlook stopped accessing Gmail
I’ve had a couple of questions this week from users who changed their Gmail password and Outlook stopped syncing the mail.
If the account is set up as IMAP Outlook should ask for the new password in a dialog box or browser window containing the Gmail log in page.
If you are using POP3 or get the regular Outlook password screen, you need an app password.
You can get a new app password in your Gmail account settings, at https://myaccount.google.com/u/0/apppasswords
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