problem with logical formula for conditional formatting

Hello everyone,

Just had a question on here but already I'm stumped again. I'm using conditional formatting to shade entire rows based on the text a given row contains in the E column. If "cash" is anywhere in the E column for that row the whole row turns yellow and if "check" is anywhere in the E column for that row the whole row turns green. Now I simply want all rows that aren't green or yellow to turn red. I was attempting to do this by negating what I used to achieve the yellow and green shading. For those I used =SEARCH("whatever",$E18) where whatever was really cash or check for the conditional formatting formula. For this, I was attempting to use =NOT(SEARCH(OR("cash","check"),$E18)). My thought was that if SEARCH found cash or check in that line it would return TRUE and then the NOT would negate it for so those lines would not be shaded, and if SEARCH didn't find cash or check in that cell then it would return a FALSE that would be negated by the not and so would be shaded. What am I missing?

Thanks again in advance.

So both of these actually turn stuff red (which is a first for this sheet), but both also turn things red that shouldn't be (things with just "cash" or "check" in the E column for that row) and don't turn everything red that should be red (misses some random rows that don't have "cash" or "check" in the E column).

Both of your posted solutions shade the same rows red (hmmmmmmmm...) but many of the rows they shade were green or yellow before (i.e. had only "cash" or "check" in the E column for that row) and it misses some random cells on my sheet as well... keep in mind that this is the third conditional formatting formula applied to the same range of cells, I'm not sure if that is affecting anything. I'd like to attach the sheet but unfortunately I can't (NDA's).

I just tried: AND(NOT(ISNUMBER(SEARCH("check",$E18))),NOT(ISNUMBER(SEARCH("cash",$E18)))

which is very similar to what ChemistB did and the same rows got shaded red... but those rows still include many that only have "check" in the E column. Quite confused as to why that is the case... some random rows that had nothing in the E column also did not get shaded while a lot of them did.

Both your solutions work on the sheets you attached, neither work in my sheet that does have E18 as the first cell in the range. I must be doing something really stupid to throw it off? I am just gonna attach the sheet quick (with most of the stuff pasted over by an unrelated soccer spreadsheet, yet still with the same problem).academy_reserves_index.xlsx

YES! So that was it, every time I would enter in the formula and then change the "applies to" range afterwards, never checking the cell references for the formula again.

Thanks very much to both of you for your help and patience.