IFERROR Not working for NETWORKDAY

Nlondon

Here is the formula I am trying to use, ideally the cell would just be blank if there was an error. I've tried rearranging in almost everyway I can think but I still keep getting #UNPARSEABLE.

=IFERROR(NETWORKDAY([Estimate Status Date]@row,[Proposal Sent]@row)"")

Thanks in advance!

Paul Newcome

You need a comma after the first closing parenthesis.