Cause

On a page in the project, no value has been entered for the property selected in the Number of pages / page name per property setting.

Solution

1. In the Message management dialog, double click on the message to locate the relevant page in the tree view in the page navigator.
2. Use the popup menu to open the Page properties dialog for the page and enter a value for the property specified in the message text, which you selected in the settings for the pages (command path: File > Settings > Projects > "Project name" > Management > Pages > Number of pages / Page name per property).
3. Select the command Number of pages / page name per property. (To this purpose you first have to Customize the ribbon and then assign the desired command to a user-defined command group.)
   
   The result is written to the Number of pages per property, Page names per property and Page counter per property page properties.
4. If required, start a new check run.