I am trying to compare dates and times on two separate sheets. On Sheet1 I have a list of dates and times as m/dd/yyyy hh:mm. On Sheet2 I have a list of dates and times as m/dd/yyyy hh:mm. I use this formula in Sheet1:

Formula: copy to clipboard 
=IF(A1>'Sheet2'!A1,TRUE,FALSE)


which returns FALSE even though it should return TRUE. If I then enter the contents of Sheet 2 into Sheet 1 and use the formula:

Formula: copy to clipboard 
=IF(A1>A2,TRUE,FALSE)


it correctly returns TRUE.

It's the exact same data! Why is this happening?

Yes, I know I can just copy the Sheet2 data into Sheet1 to get it to work, but it's inelegant and it gives me extra columns to hide (this data should be hidden from the person receiving the output) instead of just hiding a sheet. It's driving me nuts!