Ektron CMS400.Net Reference
To enable Version 7.6.5 Calendar functionality, make the following change to the siteroot\web.config file.
<add key="ek_enableClassicCalendar" value="True"/>
Both versions of the Calendar may exist on a Web Site.
For more information about using Calendar Version 7.6 and earlier, refer to Calendars in the Version 7.6 Ektron Administrator Manual.