Use this window to generate and define the period intervals the demand planning server will use for forecasting. Note if you are setting another period version than monthly, you should also consider to change some of the best fit forecast model limits. See Registry Settings for details. When setting up period versions you need to consider the allotted time intervals. You are not allowed to have any holes or overlapping entries. To validate that you have entered dates correctly you may run the Validate Dates method. If everything is ok the Date valid flag will be checked, otherwise an error message describing the problem will appear. Note that after an upgrade the flag will be switched off for all period versions and you need to run the method to validate your setup.