
Excel VLOOKUP Function — How to Use It, and the 4th Argument That Breaks It
VLOOKUP looks down the leftmost column of a table and counts N columns to the right — that one-directional design is the source of every bug it has. Learn why the 4th argument (range_lookup) must almost always be FALSE, why VLOOKUP can't look to the left, why a hard-coded column number silently breaks when you insert a column, and how to fix the #N/A that means 'not found'.





































































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