When running [Optimizely DXP](🔗), you can create a customized maintenance page, to be displayed if you have to take down the site during for example deployments. Create an HTML page called _maintenancepage.htm_, and add it in the root directory of your application, to be used for deployments.
Prior to Optimizely Content Management System (CMS) version 12, the maintenance file size should be between 512 bytes and 1 MB. CMS version 12 removes this restriction.
If you do not add this file, a generic maintenance page is used.
[Deploying: Important notifications](🔗)