=IF(ISERROR(A1-B1),0,MAX(0,A1-B1)) assuming that you might want it to show
A1-B1 in the cases for which you haven't specified an output.
or
=IF(ISERROR(A1-B1),0,IF(A1-B1<0,0,"whatever answer you want in this case"))
--
David Biddulph

FJ wrote:
Hi, I'm trying to write a formula in column C. Basically, if the
result of A1-B1 is either a negative number or gives an error
message, such as #VALUE, I want cell C1 to show 0. I realize this is
probably very simple, but I am really stumped. :( I've tried many
different combinations using IF, OR, and ISERROR but so far I haven't
had any success. :( Can anyone help?

Thank you in advance for any information.