Quick Preview, the recommended option, presents customers' sites as subdomains of one of your domains. Note that if you do not specify a preview domain, the site preview function will be unavailable to your customers.
(Default) Limited Preview is used in earlier Panel versions; it presents customers' sites as directories under the Panel server. This mode has two major drawbacks: Only authorized users can view such websites and some scripts and Flash animation might not work well on them. We recommend to use this mode only before the Quick Preview is configured.
To switch between Limited Preview and Quick Preview, use the following steps.
1. Log into Plesk.
2. Click on 'Tools & Settings' under 'Sever Management'.
3. Click 'Website Preview Settings' from the General Settings section.
4. Select Quick Preview and enter the external domain you would like to use.
5. Click OK.