thinapp msi and reinstall

Hi,

With thinapp packages it's possible to deploy with msi options.

For example : msiexec /i mypackage.msi /qb

But if i want to reinstall or repair my package who is already install in a computer how to do ?

I have try

msiexec /faums mypackage.msi /qb

but not work (error msi already installed)

Have you solution ?

Regards