These instructions also apply for when you just want to completely uninstall the AutoCAD based program(s) from the computer, or if your installation of the program did not complete successfully and you need to clean out the failed installation.
Follow the steps of this document to remove the software:
Removing all Autodesk® software products from system to ensure a clean installation:
http://usa.autodesk.com/getdoc/id=TS45252
If Add or Remove Programs is not working for you, skip that part of the document, follow the manual file removal process in the document, and then use the Windows Installer Cleanup Utility at the link farther down in these instructions.
If you only want to remove one version of the product, or one Autodesk program and not the others, just go down into the parent folders and registry entries indicated in the document and find the product-specific folders you need. If you follow the directions of the document as written, it will remove all Autodesk programs from the computer.
To verify that Windows sees the program as having been uninstalled, you can use the Windows Installer Cleanup utility, available from a third party website at the link below:
Windows Installer CleanUp Utility:
http://majorgeeks.com/Windows_Installer_CleanUp_Utility_d4459.html
NOTE: This utility only removes whatever setting is telling Windows the program is there. It does not actually uninstall the software. You need to use the normal Add or Remove Programs utility first. If you use this cleanup utility first it will remove the program from the Add or Remove Programs list so you cannot uninstall it normally.
If you just wanted to remove the software, you are done at this point.
When you get ready to reinstall the program, if that is your intention, follow the process of the document below:
Clean installation on Windows® XP:
http://usa.autodesk.com/getdoc/id=TS75218