I am trying to make it so the schedule at my work (done in excel) will check the times a person is sceduled against the master availability. That way, if someone is mistakenly scheduled at a time when they are not available, a notice saying "Unavail" will appear. I believe I have the correct formulas to do this, but it is not working. I was hoping that one of you who may know more than me about Excel can give me a hand. Here is the formula in the cell: =IF(C8=0,0,IF(D8=0,0,IF(C8<'[Test 2.xls]Managers'!$C$8,"Unavail",IF(AND(D8>'[Test 2.xls]Managers'!$D$8,'[Test 2.xls]Managers'!$D$8<>"Close"),"Unavail",IF(D8>C8,(IF((24*(D8-C8))>=5.5,(24*(D8-C8))-0.5,(24*(D8-C8)))),IF(D8<C8,(IF((24*((D8+1)-C8))>=5.5,(24*((D8+1)-C8))-0.5,24*((D8+1)-C8))),"")))))) The formula as a whole states: If C8 (start time) or D8 (end time) is = to 0, then the cell will come up as 0. If not, then if C8 is less than the opening time for this person on the Master Availability sheet (I saved that sheet as "Test 2) the cell will come up as "Unavail." If not then if D8 is greater than the closing time for on the master availability, AND the master availabilty sheet does not say "Close", then the cell will come up as "Unavail." (I have to put in that "Close" part, as we are often scheduled to 1:30AM, I can't just have the greater than part because if someone is sceduled to 5:00pm, but is available till 2:00 AM, the cell will come out as unavail because 5:00pm is greater than 2:00 AM) If not, then the rest of that basically figures out the amount of hours in decimal form minus a half hour break if the shift is more than 5 and a half hours. So my problem area is the area bolded. There is something wrong with that formula that I am not seeing. I've attached the two files, Since it is an actual schedule, I deleted everyone's name, to protect the innocent or something. I have only tested the formula on the Manager tab for the "Salary Form" (which does not calculate out a break) and for "Joe Shmoe" but only for Wed the 31st. If someone could give some advice that would be awesome.