You need run the secondary installer to reset AutoCAD 2011 or AutoCAD LT 2011 to the default settings.
First, you must first delete your application files and registry entries for the program. Follow these steps:
Important! Make sure that you back up any customized AutoCAD 2011 or AutoCAD LT 2011 files before performing this procedure.
Click Start menu (Windows) > Run.
In the Run dialog box, enter regedit
In the Registry Editor, locate the following subkey and delete it:
AutoCAD LT 2011:
HKEY_CURRENT_USER\Software\Autodesk\AutoCAD LT
Exit the Registry Editor.
In Windows Explorer, locate and delete the following application folders:
AutoCAD LT 2011:
C:\Documents and Settings\
\Application Data\Autodesk\AutoCAD LT 2011
C:\Documents and Settings\\Local Settings\Application Data\Autodesk\AutoCAD LT 2011
Start AutoCAD LT 2011.
The files and folders that were deleted will be recreated by the secondary installer
Emily Xu
Product Support