hiding 0 from a cell

Giganews Newsgroups
Subject: hiding 0 from a cell
Posted by:  billy_bags
Date: Mon, 29 Jan 2007

I can't figure out why this doesn't work, I keep getting circular references.
i have 3 workbooks. 1 is a summary linked to other 2 which are stored in a
different drive. The summary is I:\abc\etc\[summary.xls]sheet 1'!$d$6).
At the moment the cell inwhich this reference sits has 00:00  which is
mm:ss. I want this cell to remain empty until the cell from which it is
linked is populated with a figure.
so =if(c4=0,'','I:\abc\etc[summary.xls]sheet1'!$d$6)

The response is "the formula you typed contains an error  etc etc.
I followed what I thought I had to but no joy.
Any help would be appreciated,