From another post, if Bob's is not it:
Re: Open files from windows
try this in Windows Explorer, Tools, Folder Options, File Types, pick DWG,
select Advanced, highlight Open, pick Edit, Check Use DDE, in the DDE
Message type in
open("%1")
OK, OK, close,
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Dean Saadallah
Add-on products for LT
http://www.pendean.com/lt
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