Uninstall problem with window NT 4.0

[SiriusGG]

I have a problem with the uninstaller.

I created a setup with installscript (setup.exe project), which can make
a new installation, a repair/update and an uninstallation.

It seems in Windows 4.0 NT, in OnMaintUIBefore. I cannot get nType to
equal RemoveALL.
My code works in Windows XP finde.
But when i go to Add/Remove programms in Windows NT it installs the
application instead of uninstalling it.
It seems to me the value is never being set to REMOVEONLY !
So i cann't make an uninstall in Windows NT 4.0 !

What is the problem !