Can I Add Custom Subdomains Or Multiple. Rather than registering a new domain name you can always create a subdomain using a domain you already own for example blogdomaintld or forumdomaintld assuming you already hold domaintld. If you are letting Microsoft manage your DNS settings with NS records you cant add subdomains.
I understand I need to do. The landing page URL for your landing pages now contains the subdomain domain name and directory. Typically you can add up to 900 domains to your Office 365 subscription.
If desired click the Make Primary button next to your new domain.
Custom CNAME records Step 1 is to set up custom awverify CNAME mappings from each domain to Azure for verification so that Microsoft knows that you owncan administer the domain. Many people mean only the third-level domain when they say subdomain or fourth-level domain in case of an effective top-level domain like couk probably because most domains dont have more levels however. The landing page URL for your landing pages now contains the subdomain domain name and directory. Typically you can add up to 900 domains to your Office 365 subscription.
