>Seems to me this is counterproductive. Why not just use the doggone number 16? Otherwise, you have to remember to do the #DEFINE or attach the .H file.

I like Constants: what are you going to get with:

?aErrorArray[1, 3]
?aErrorArray[1, 4]

? How about:

?aErrorArray[1, cnAERROR_LINENO]
?aErrorArray[1, cnAERROR_METHOD]

It may take a while in the beginning to learn them (but not as long as the numbers) for putting them in, but it will always be simpler reading.