Microsoft 365 alias setup

Use this if you have several aliases on one Microsoft 365 mailbox — support@, info@, sales@ — and you only want one of them in Commslayer. The rest stay in Outlook.

Time required: 15–20 minutes

Not what you need?

Before you start

  • Admin access to your Microsoft 365 account
  • Access to your domain's DNS settings

Step 1: Create your inbox and add DNS records

Use your alias address as the inbox email — support@yourstore.com, not the mailbox's primary address.

Step 2: Enable external forwarding

Microsoft 365 blocks external forwarding by default.

Enable external forwarding in Microsoft 365 →

Step 3: Create a rule for the alias

Instead of forwarding everything, target the one alias:

  1. Sign in to outlook.office.com

  2. Click the gear icon → View all Outlook settings

  3. Go to Mail → Rules → Add new rule

  4. Name it (e.g. "Forward support alias to Commslayer")

  5. Under Add a condition, select To and enter your alias

  6. Under Add an action, select Forward to and paste your Commslayer forwarding address

  7. Optionally add Move to a separate folder, so these stop cluttering the mailbox

  8. Save

If the alias is on a shared mailbox rather than a personal one, set this up as a mail flow rule in the Exchange admin center under Mail flow → Rules instead.

Step 4: Test

Send a test email to the alias from an outside account. It should land in Commslayer. Mail to your other aliases keeps arriving in Outlook as normal.

Microsoft quirks

  • Other aliases are also reaching Commslayer. Your rule's To condition is too broad — it should name only the support alias.

Anything else? Email troubleshooting →