404 Error with Custom Domain

Sue Folkerts 16 Reputation points
2021-03-11T00:23:19.447+00:00

I am using a custom domain and when I click Troubleshoot on the custom domain tab it comes up with no problems. When I access from the same machine, where I set up Azure it has no error. On either of the other two machines I have it give a 404 error. On my tablet it works fine. Why does it have a 404 error on the other two machines, one is my laptop, the other a school supplied laptop.

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  1. brtrach-MSFT 15,791 Reputation points Microsoft Employee
    2021-03-11T22:11:28.687+00:00

    @Sue Folkerts Thank you for your question.

    There are two issues that come to my mind that might be causing the 404 error.

    1. DNS propagation. Sometimes it can take up to 30-45 minutes for the DNS to be fully updated with the new custom domain. This means some computers might be able to access the site before others.
      1a. There also might be browser cache coming into issue. Be sure to use an inPrivate browser session to ensure your browser hasn't cached the 404 error page
    2. You only put in an DNS entry for the root domain and not the subdomain or vice-versa. So maybe on your primary machine you're going to www.contoso.com and that works because that's your DNS entry. But maybe on your two other machines, you're going to contoso.com but that's giving a 404 error because there is no DNS entry for the root domain, contoso.com.

    Can you please verify if it was a DNS delay issue or whether or not you've added both the root and subdomain? We look forward to your reply.