Rhino 4.0 and 32-bit Rhino 5 crash while trying to browse for a .dwg file from the Open, Insert, Import, Save, SaveAs, or Export commands.

Your computer has

• 64-bit Windows Vista or 64-bit Windows 7.
• AutoCAD 2005, 2006 or 2007. (AutoCAD prior to 2008 does not detect the mode of the OS and installs as a 32 bit application.)

AutoCAD 2005, 2006 or 2007 installs a shell extension called AcSignIcon.dll. This shell extension loads into Rhino's File Open dialog box. This shell extension often causes Rhino to crash while browsing for .dwg files.

Disable the AcSignIcon.dll Shell Extension:

1. Download DisableAcSignIcon.zip.
2. Extract DisableAcSignIcon.reg.
3. Double-click DisableAcSignIcon.reg, and follow all the prompts to allow the .reg file to modify the settings on your computer.

Information about other shell extensions that crash file open dialogs.