ISScript8.Msi Silent install through WPI ...Doesn't work ? Need he

[Godflesh]

I got this commandline in Windows Post Install Wizard...and it won't install.

cmd1[pn]=['msiexec.exe /i "%wpipath%\\Install\\Video Editing\\ISScript8.Msi" /norestart /qb']; <-- what is wrong with it? (it is command 1 of 3 in total)...but I need to install ISScript8.msi first.

Please help