If you think this message is appearing erroneously, make sure that it is not caused by one or more of the a-e-i-o-u sets being selected in the Holidays Override property of one of the DiaryGridLines.
This can be due to either of the following :
•Use of the Compiler Directive INCLUDE_MACRO.
•Reference to a Holidays List in the Initial Conditions of the Macros property.
Consequences : The part of the Macro related to this Holidays List will never be performed, presumably causing problems with you Macro.
•Change List of Holidays Sets : Opens the corresponding Holidays List property editor, so you can select one or more Holidays Sets to use.
•Edit Holidays Rules : Let you add/modify holidays rules.
•Use one of the prefered Holidays Sets : At the bottom of this popup menu, you will find the "favourite" Holidays Sets as you have selected them in International Preferences. Note that you can only select one Holidays Set using this solution.