wamatt: Sorry for not replying earlier. The trick is that if you need to pass any switches to msiexec, you have to "escape" them. That means use backslashes. For example, for the line you needed: start /wait AdbeRdr60_enu_basic.exe -p"-s /v\"/qn INSTALLDIR=\"c:\Progs\Media\Adobe\Acrobat 6.0\"\"" See that I escaped every set of double quotes except the first and the last ones? And if you need that inside your RunOnceEx.cmd file: REG ADD %KEY%\001 /VE /D "Adobe Acrobat Reader 6" /f REG ADD %KEY%\001 /V 1 /D "start /wait AdbeRdr60_enu_basic.exe -p\"-s /v\"/qn INSTALLDIR=\"c:\Progs\Media\Adobe\Acrobat 6.0\"\"\"" That is, of course, escape another set of double quotes since you need to enclose the line you need to install the program between "s. Another example would be what I actually use and works for Diskeeper 8: REG ADD %KEY%\002 /VE /D "Diskeeper 8" /f REG ADD %KEY%\002 /V 1 /D "%SYSTEMDRIVE%\Applications\diskeeper\setup.exe /s /v\"/qn INSTALLDIR=\\\"%PROGRAMFILES%\System\Hard Drive Tools\Diskeeper\\\"\"" /f pastl (or anyone willing to help, actually): Your tips were very useful, thanks a lot for them. The only problem I am having is that none of the installation programs made with Wise installer seem to like the /X switch. For example, Opera 7.51 just won't install if I use /X. Instead, the installer extracts the installation files to the directory of my choice but never actually installs the software. In fact, after reading Wise KB Article #564 I found out the following: /X pathname -- extracts files into pathname So I guess that Wise just doesn't have a switch for installing to an alternative directory, and that's why I just repacked the applications that use it and well, it seems that they work. Anyway, if anybody of you does know how to make Wise Installer install an application to a directory other than the default, please post your comments.