I generally use an IF statement and ISERROR so :

IF(ISERROR(INDEX)=true,0,INDEX)

Since this gets to be a pain keeping up with all the (( and )) start

by typing your formula then put an

ISERROR( at the front and a ) at the end.

This should return TRUE.

Then just put an IF( in front of all that and at the end

=TRUE,0,<paste formula> and a ) and that should do it. Basically

you are saying IF the formula returns an error insert a zero if it

will work run it. I do not like posting a formula without being able

to replicate it but it should look like this :

=IF(ISERROR(INDEX(JULY!$A$6:$F$800,MATCH($A3,JULY!$A$6:$A$800,0),3))=true,0,INDEX(JULY!$A$6:$F$800,MATCH($A3,JULY!$A$6:$A$800,0),3))

Hope this helps.

Chad