Qdabra's Query Builder InfoPath form tool needs to
run with full trust so that it can execute shell commands. To install
this full trust tool on your local computer, we use InfoPath’s built-in
support for URN based solutions. When the form is installed, InfoPath
adds entries to your Windows registry. Unfortunately, due to a bug in
InfoPath installer, sometimes uninstalling doesn’t work and the registry
entries are not cleaned up correctly. In such cases, the result is that
you can’t re-install the tool, since your machine will think that "The
form is already installed on your computer". You might also find that
you are unable to remove the form from the InfoPath cache when you run
the command Infopath /cache clearall.
If you encounter this issue, try to remove the form
using the Windows CleanUp
Utility. In addition, you might need to manually clean up the
registry. Do this at your own risk and backup your registry before
proceeding. If the problem is happening with the QueryBuilder form, for
example, search for "QueryBuilder" in the registry and you will find a
key like this:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\InfoPath\SolutionsCatalog\urn:schemas-microsoft-com:office:infopath:Qdabra-Query-Builder:-myXSD-2008-02-19T23-06-28.
Remove this key manually and you will then be able to
reinstall the form.
Note that this could happen with any installed form,
not just the QueryBuilder form.