[wix-users] Wix dual mode package: perUser installation error + perMachine doesn't upgrade

[Suhaib Ahmad]

I have made an installer using WixUI_Advanced template and modified the
WixUI_Advanced.wxs by following these two links:

http://uvinw.com/per-machine-and-per-user-without-UAC-in-WiX/
http://www.egoroff.spb.ru/blog/62003.html

I am trying to release an installer that can allow both perUser and
perMachine installation. The installer should replace an old application
installed and overwrite it if it is of the same InstallScope.

The problem I am facing is that when I do a perUser install, I get an error
right at the end of the installation that "*There is a problem with this
Windows Installer Package. A program required for this install to complete
could not be run. Contact your support personnel or package vendor.*" After
that the installation just rolls back.

Moreover, when the same application is previously installed(perUser) and I
run this installer as perUser, it uninstalls the old one, shows the same
error for the installation of the new one, and rolls back. In the end
neither of the application remains on the machine.

The perMachine installation runs fine, however, it does not replace the
previously installed old application. Instead, it simply installs and there
are two entries in the control panel's programs and features.

I am pulling my hair because of this, and please any help would be greatly
appreciated.

Thanks
Suhaib