When starting ProStructures for AutoCAD default Drawing1 opens instead of a ProStructures Project.
To keep a default Drawing1 from being created you can set the AutoCAD startup variable.
Steps to Accomplish
Using Startup variable
1.) Type Startup and the command prompt and select the <Enter> key
2.) Type 2 and select the <Enter> key.
Now when you start AutoCAD there should be no Drawing loaded unless customization has been added.
What are the settings?
0 = Displays the Select Template dialog box, or uses a default drawing template file set in the Options dialog box, on the Files tab
1 = Starts without opening a drawing template file, and displays the Startup or the Create New Drawing dialog box
2 = Starts without opening a drawing template file, or if available in the application, a custom dialog box is displayed
(AutoCAD 2007 only has options 0 & 1 available.
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