=IFERROR(1/0,"a")
Returns A

I tried a different route shown below and got a circular error.

=IFERROR(VLOOKUP(A2,UPCLOOKUP,FALSE),IFERROR(VLOOKUP(B2:Y63014,23,FALSE),IFERROR(VLOOKUP(ProductMaster!B2:S149824,18,FALSE),””)))