Good practice would generally recommend that you eliminate the #N/As,
instead, to avoid having "expected" errors. If they're being generated
from a lookup, you can use something like

=IF(ISNA(VLOOKUP(...)),"Not Found",VLOOKUP(...))

in which case SUM will ignore the text.

You can, though, use this array-entered (CTRL-SHIFT-ENTER or CMD-RETURN)
formula:

=SUM(IF(ISNA(A1:A50),0,A1:A50))

In article .com,
wrote:

Hi,

Can anyone please let me know how can I add some values in a column
which contains some #N/A.

Thanks.

MH