When double-clicking a DWG file to open it in AutoCAD, one of the following occurs: .
Temporarily turn off User Account Control (UAC)
Nothing happens and no error message is shown. A message appears from the operating system about not knowing which program to use. A program other than AutoCAD starts and tries to open the file. The Windows registry entries for DWG and other AutoCAD file type associations are invalid, damaged, or missing. 'AutoCAD DWG Launcher' is not associated with DWG files.
Make sure that the DWG file or folder is writable
Insufficient user or application permissions. User Account Control (UAC) is set too high. Corrupted Windows user account. Use the OPEN command within AutoCAD. Drag and drop DWG files onto the desktop shortcut for AutoCAD. To resolve the double-click problem, do one or more of the following (test double-clicking a DWG after each suggestion): .