When you add
existing item, select this item in "Add existing item..."
dialog and from pull-down menu on "Open" button (little triangle on the
right side) select "Link File". This will only link existing file and
will not create any local copy.
> I'm sure that this has been asked many times before but there isn't enough
> history in the newsgroup for me to find it.
You can use Google's web interface for all MS newsgroups if you need to
search the history. For example, use
http://groups.google.com/group/microsoft.public.vsnet.ide to see this group.

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Peter Macej
Helixoft - http://www.vbdocman.com
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