Coloring two rows: IF: comparing duplicates in two columns with a third boolean column

Hi,

Quite new to Excel to this extent. I'm trying to build up an inventory list, and as a result, a sheet for borrowing equipment.

I need to compare duplicates in A and B to a boolean in E, if it's not returned and I try to add in someone borrowing equipment, I need equipment and ID-number to turn red.
So when Rachel is trying to borrow the multimeter in A12, the moment the formula reads duplicate in A and B, and False in E, A12 and B12 will turn red
Also when Martin try to borrow the drill again in A13, it will turn red because of the same reason

I'm trying =IF((AND(A2:A15, >1),(AND(B2:B15, >1))(AND(E2:E15, "No")))
(BTW, I see that I forgot to add the B-column in the example, nvm that)
But to no avail. I've spent 10 hours on searching just on blind stubbornness. Have I ventured too far out in newbie-land?

Please help!