I hope I'm not violating any agreements by posting help I received from Autodesk through our subscription, but here are some quotes from a message I received concerning the dreaded 1402 error (note that some of this applies to Windows 7, not to XP):
----------------------------------------------------------------------------
... I will be working with you to resolve this case where you are getting the 1402 error with the incomplete registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Autodesk\\RegistryVersion17.0.
However, when applying the patch, the Windows Installer service is unable to correctly resolve this path as it should actually be the following:
HKEY_LOCAL_MACHINE\SOFTWARE\Autodesk\Inventor\RegistryVersion17.0
Since we worked on the original case related to this same issue last summer, I discovered that the Windows Installer service sometimes will incorrectly resolve the path, making it incomplete as in the first path above, when the user permissions launching the install are reverting to the User level instead of the Administrator level of permissions.
To test this, please verify the accounts listed with permissions to the key, by right clicking on the Autodesk key and select Permissions:
HKEY_LOCAL_MACHINE\SOFTWARE\Autodesk
Make sure that the Users\<account_name> as well as the Administrators\<account_name> have full permissions to this key. I was able to work with another user who experienced this error and setting the full permissions for the User account on this key as well as the Administrator, resolved the issue and the patch was able to apply successfully.
Also, verify that the User Account Control Settings are set to the minimum level during the install sequences. The following link provides additional information on the behavior of the different accounts when the UAC is in effect:
http://technet.microsoft.com/en-us/library/cc709691(v=ws.10).aspx
Unlike earlier versions of Windows, when an administrator logs on to a computer running Windows 7 or Windows Vista, the user’s full administrator access token is split into two access tokens: a full administrator access token and a standard user access token. During the logon process, authorization and access control components that identify an administrator are removed, resulting in a standard user access token. The standard user access token is then used to start the desktop, the Explorer.exe process. Because all applications inherit their access control data from the initial launch of the desktop, they all run as a standard user.
After an administrator logs on, the full administrator access token is not invoked until the user attempts to perform an administrative task. When a standard user logs on, only a standard user access token is created. This standard user access token is then used to start the desktop.
I'm including a link to a Forums post from David Lau that also contains additional background on this issue:
http://forums.autodesk.com/t5/Autodesk-Inventor/Instalation-error-1402/td-p/2951156
http://forums.autodesk.com/t5/Installation-Licensing/Error-1402-during-uninstallation-Could-not-open...
------------------------------------------------------------------------------------
