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Symptom

You want to use a domain or subdomain in your webspace account as part of your Wordpress multisite installation. This means that if you open the domain in the browser, the displayed content should come from your Wordpress installation, without you having to do another Wordpress installation in the domain.

Solution

Always follow the Wordpress instructions for setting up a multisite installation. The only thing you need to do in the web server is to put your domain's root of documents in the same directory where the Wordpress installation is located. The best and safest way to do this is to set up the domain or subdomain as the "alias" of your main domain. If you add the subdomain or domain as a domain that is managed separately from the main domain, you are risking backup and later recovery errors because the web space control panel cannot reliably detect that the data of the main domain must not be overwritten by the "empty" content of the subdomain or additional domain.

Do not add your sudomain or domain with "Add domain" or "Add subdomain", but with the "Add alias" button. If you have already set up the domain, first remove it from the webspace control panel and then re-add it as an alias. Note that after every change to the web server configuration, it may take up to 15 minutes for the change to take effect.

Overview of frequently asked questions