Error ! Content controls are allowed only in content page that references a master page

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Content controls are allowed only in content page that references a master page.
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This error occurs when the webpage that contains a content element,
does not have any master page.

For example,
<%@ Page Language="VB" MaintainScrollPositionOnPostback="true" %>



will raise an error.

Either remove the Content controls or include appropriate master page

Solution:
<%@ Page Language="VB" MasterPageFile="~/MyMast.master" MaintainScrollPositionOnPostback="true" %>