Office 2007 upgrade doesn't remove Office 2003

We have few systems in a small setup running with Office 2003. Last month we just upgraded all Outlook to 2007 version using MSP and left all other Office apps to 2003. Now we want to update all those left office apps too to version 2007 but without touching already updated Outlook. Hence we cannot directly run setup.exe /adminfile because of outlook. So what I did is I made some customization in the MSP file so that it will install Office 2007 on all PC as well as remove Office 2003. I tried doing run: msiexec.exe /p customization.MSP.

Well the process was successful but partially. It installed office 2007 and everything is working but it dint uninstalled Office 2003. Though there is no problem as both versions are working fine but to prevent any problem in future I want to remove Office 2003 but not manually. Can somebody help?

I think you should try out some command line or any script to uninstalled Office 2003. It should be something like :

Setup.exe /x <path>\<product>.msi /qb-

Or if you want it without UI than you can use “'/qn' for '/qb-'.”