Installation fails on NT4 Terminal Server - General MSI

When we try to run our setup on a NT4 Terminal Server with Citrix MetaFrame directly on the server (as an "All Users" installation) the following situation occurs:
1. The setup tries to access drive C:, which is not present, before the UI appears. The server is configured with the system on drive M: and a temporary user directory on drive H:, containing a "fake" Windows directory for storing *.ini-files of 16-Bit-applications
The first problem (drive C:) could be circumvented by mapping the drive to a directory using the "subst" command.
2. After finishing the user interface sequence the setup fails with the message "Invalid drive H:". It seems it searches for some windows components in there, but the system is placed on drive M:

We created the setup using ISWI 1.5. It also contains some Merge Modules (MFC-Dlls, DCOM, MS-Chart, VB-Runtime and so on). The customer describing the problem is using an NT4 Terminal Server and Citrix-Workstations.

Help is urgently needed!

Many thx,
ReneMT

(Edited by renemt at 4:48 pm on Sep. 28, 2001)