This is a little something I was suffering with for about 3 hours the other morning…
Trying to create a all day event from a SharePoint 2010 workflow using SPD, seems rather simple.
Open a calendar list, create an event using the default form.
Select “All Day Event” and save it, woohoo, now lets look at the list view for the calendar
Now isn’t that just dandy, just make sure you set “All Day Event” to “Yes”.. man I love SharePoint..