Cannot reinstall a Named Instance of MSDE

I wonder if anyone can help me figure out the solution or point to the
solution.
I have a Windows 2003 Server SP1 running 3 Named Instances of MSDE
(Microsoft ISA Server Firewall, Panda Antivirus Administrator and Symantec
Backup Exec for Windows) I had major problems where the Backup Exec Server
service would hang on the "Starting" state so I decided to uninstall Backup
Exec V.10 SP3 including it's Named Instance MSDE. Because I had the MSSQL
BKUPEXEC service stopped it said I had to disconnect the BEDB myself. I
continued and proceeded to delete the BKUPEXEC directory on the Program
Files\SQL Server directory. I tried to reinstall Backup Exec but it kept
stopping and rolling back the action. The log said that it failed while
installing a Third Party application, namely, MSDE. I then proceeded to
install MSDE manually but it kept rolling back the install. This is the
syntax I was using: Setup.exe INSTANCENAME=BKUPEXEC DISABLENETWORKPROTOCOLS=0
SAPWD=Pinoy69 TARGETDIR="C:\VERITAS\MSDE" /L*v C:\msde_BKUPEXEC.log
The msde_BJKEXEC.log kept giving me a MainEngineThread is returning 1603.
I have been working on this problem for the past 2 nights and I can' think
anymore.