At this time it is hard to know what the Manual/Automatic condition state was. However, I have in my Workbook_Open and Workbook_BeforeClose logic that asks if Calculation is set to manual, and if it is, it changes it to Automatic, then executes a Msgbox that tells me about it so I can look for the reason. I kinda think it was not Manual, but it's something I have to wait a week for in order to tell. My conditions are VERY time oriented, and this situation only occurs on a Friday. I'll check it out though. I might say that once the conditional format executes, it is stable, i.e., it doesn't happen each time I open the workbook.