=MAX(IF(NOT(ISERROR(A1:A100)),A1:A100))

which is an array formula, it should be committed with Ctrl-Shift-Enter, not
just Enter.
Excel will automatically enclose the formula in braces (curly brackets), do
not try to do this manually.
When editing the formula, it must again be array-entered.

You also cannot use whole columns in array formulae, it must be explicit.

--
HTH

Bob

(there's no email, no snail mail, but somewhere should be gmail in my addy)

"hmm" wrote in message
...
The function =MAX(A:A) is giving a #N/A error because some of the cells in
column A are errors.

Is there a way to tell MAX to ignore errors (perhaps by putting A:A into
some sort of filter function)?