How can I avoid an #N/A appearing in a VLOOKUP?

[Marcl]

A 20 D 40
C 30 A 20
D 40 F 60
E 50 E 50
F 60 G 70
G 70 C 30
H #N/A
In this simple example, I need the H value (on right) - which is not in the
original data sheet (on left) to return a non-#N/A. In this example, i would
want to sum all the numbers but of course cannot because of the #N/A
Any help would be appreciated.
Thanks, Marc

 

[-a]

I use an If (error( statement like:

The error captures the #N/A Result. It should look something like:

If(iserror(vlookup(x,y,z)),"-",vlookup(x,y,z))

 

[Carolina]

In two formulas like mine where would I put the iserror statement??? I've
tried it and I get errror messages

=IF(D5<=0,VLOOKUP(F5,Sheet2!$A$3:$C$1873,3,FALSE),VLOOKUP(D5,Sheet2!$A$3:$I$1873,9,FALSE))

and

=IF(P5>=Sheet2!$A$1874,Sheet2!$B$1874)


Thanks!
Carolina