AutoCAD 2008 with Windows 7 > Every Drawing Opens a New Session

Hi All,
I am using Inventor 2008 and recently switched over to Windows 7 from XP. The problem I'm having is this, when I double click a dwg from
explorer, Inventor launches instead of AutoCAD. No problem, I'll just default dwg's to open with AutoCAD instead of the DWG Launcher application. That works fine; but now when I open from explorer, I get a new session of AutoCAD for every drawing I open. I want each drawing to open in the same session, this prevents a million tabs in the taskbar and all my macros from having to reload every time. I need to open a lot of drawings quickly throughout the day, so the file>open routine is not a great option for me; although it does solve this problem. Does anyone know how to fix this problem? Thanks, Paul.
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Set SDI to 0
Charles Shade www.cshadedesign.com
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Thanks for your response Charles, but that's not it. SDI is already set to 0. In use, the AutoCAD application remains open constantly, only the drawings are closed. Still, each time a drawing is opened from Windows Explorer, a new session is opened. Oddly, it didn't behave this way last week under Windows 7, or in my XP installation!
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You may need to reassociate the OPEN command to AUTOCAD DWG LAUNCHER and not acadlt.exe
Either right-click on a dwg, select Open With, find the above and check the box to 'always use selected...' or get into Windows Explorer options or Windows Registry.
Something changed on the computer in the last week. I've found that sometimes a downloaded drawing will do this. Virus definition and Windows updates as well as Registry Cleaners will muck with this also.
Charles Shade www.cshadedesign.com
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Thanks Charles, The problem is that when I do associate DWG with the DWG Launcher, Inventor launches, not AutoCAD as I want. When I associate DWG with the AutoCAD application, each file opens in a new session when launched from explorer...not good.
However, I found the answer here:
http://civil2inventor.wordpress.com/2009/07/06/autodesk-dwg-launcher-wigged-out-fix /
Once you hack the registry it works fine.
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Good to know. Thanks for the follow-up. This does seem to be a regular question over in the Autodesk Forums but this is the first time I have seen that solution. Usually it has been a variable needing to be adjusted.
Regards, Charles Shade www.cshadedesign.com
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