SQL 2005 Express Edition Setup From Installshield

I tried to execute SQL Server Express Setup through InstallShield Script and it says that i required Admin Privilege. I checked and i have an Adnming privilegers.

Here is the Script. And the check says that i am an admin.

if ( Is(USER_ADMINISTRATOR, "") = TRUE) then
MessageBoxEx("Admin...","Install",SEVERE);
else
MessageBoxEx("Non Admin...","Install",SEVERE);
endif;

setuppath = "C:\Program Files\dir\Setup.exe";
sqlcmd = "ADDLOCAL=ALL";
LaunchAppAndWait(setuppath,sqlcmd,LAAW_OPTION_WAIT);
if(LAAW_PARAMETERS.nLaunchResult != 0) then
MessageBoxEx("Fail to install SQL Server Express...","Install",SEVERE);
endif;



What could be the possible reson for failr?



-timir