This article describes how to disable CAD .dwg files after you install Microsoft Office Visio 2003 Service Pack 3 (SP3).

Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

After you install Visio 2003 SP3, you can disable the use of .dwg files in Visio 2003. You may want to disable .dwg files in Visio 2003 to improve the security of Visio 2003 files.

When you disable .dwg files, the following behavior occurs:

•	AutoCAD Drawing (*.dwg; *.dxf) does not appear in the Files of type box in the Open dialog box
•	CAD Drawing is disabled on the Insert menu.
•	When you open a Visio file that contains a CAD object, the CAD object appears as a empty container. The ActiveX control on the CAD object is disabled.
•	AutoCAD Drawing (*.dwg; *.dxf) does not appear in the Files of type box in the Save As dialog box.
•	Convert CAD Drawings is disabled when you point to Add-ons on the Tools menu.
•	Convert CAD Library is disabled when you point to Add-ons on the Tools menu.

To disable .dwg files, follow these steps:

1.	Exit Visio 2003.
2.	Start Registry Editor. To do this, use one of the following methods: • In Windows Vista, click Start , type regedit in the Start Search box, and then press ENTER. If you are prompted for an administrator password or for a confirmation, type the password, or click Continue. • In Microsoft Windows XP, click Start, click Run, type regedit in the Open box, and then click OK.
3.	Locate and then click the following registry key: HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Visio\Application
4.	After you click the key that is specified in step 3, point to New on the Edit menu, and then click DWORD Value.
5.	Type DisableDWG, and then press ENTER.
6.	Right-click DisableDWG, and then click Modify.
7.	In the Value data box, type 1, and then click OK.
8.	On the File menu, click Exit to exit Registry Editor.

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