I'll admit that this posting is probably vague enough to be useless, but ...
There used to be a switch in Excel where you could set row 1 to be read as 0, so it would still be shown as row one on the side of your screen but all references to row 1 would be 0, row 2 would be 1 etc.
I know this because it screwed up one of my sheets for ages before I found out about that option. Unfortunately I can't find the switch now!!
I'll look for a while and see what I can find...