Angela,
Conditional Formatting only allows 3 conditions. You have four.
N column =1 P column = blank
N column =0 P column = something
N column =0 P column = blank
N column =1 P column = something

Formatting is applied based on the first true condition met.

Note Using multiple conditions If more than one specified condition
is true, Microsoft Excel applies only the formats of the first true
condition, even if more than one condition is true.

In other words Excel doesn't "stack up" formatting from two conditional
formatting formulas which might both be true.

Maybe one of the Excel Gurus has a trick, but I don't believe you can
do what you want.

HTH


--
Casey


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