installshield - Files not being overwritten even with REINSTALLMODE=amus -

i'm pretty new installshield - bear me.

i have created basic msi installer correctly installs our application and, until recently, every time rebuilt (with new files new build of our application), replace files no issues.

however, rebuilt morning new version, flat out refuses replace files.

for example, out main exe has file version of 8.0.0.15, 1 replacing 8.0.0.13; new modified , created date 7/11/2013, 1 replacing 6/26/2013 both - still wont replace old file new 1 (this 1 file in hundreds, main exe , gets changed each release).

i have changed properties of our own exe's , dll's 'always overwrite' under 'files , folders' no avail (i haven't touched 3rd party dll's since never changed). have changed resintallmodetext 'asum' no avail - should try 'asumv'?.

before have application uninstall prior reinstall, there else should looking @ try , determine may preventing installshield replacing files on target machine?

i have no idea have changed cause stop upgrading - haven't had make changed installshield months since running fine.

if need logs or anything, let me know (though can't write out installshield verbose log on install - can provide windows installer logs).

thanks help!

thanks comment @anand solved problem well. in case, executable not updating when updated product version (i.e. 1.0.001 1.0.002) , changing package code new build.

the solution me right-click on executable in files , folders (in installshield) , select properties. after checking "always overwrite" executable gets updated regardless of product version or package code.