I’ve recently been asked to look at an issue where a previous install of Microsoft Office 2013 with customizations such as the following were made:
… but a decision was made afterwards that these should be removed so the administrator would uninstall the installation, modify the MSP file, reinstall but noticed that Outlook would continue to automatically create a profile as defined in the previous installation.
The reason for this behavior is actually quite simple and that’s because OCT actually creates a custom15.prf (or 14 for Office 2010) within the Microsoft Office directory which contains the customizations for the Outlook profile creation:
32-Bit Office: C:\Program Files (x86)\Microsoft Office
64-Bit Office: C:\Program Files\Microsoft Office
File name: custom15.prf
The PRF file is actually a simple text file that you can open with Notepad to browse the customizations as shown in the following screenshot:
As most would have probably guessed, the way around this is to either delete the whole directly after Office has been uninstalled or simply delete the PRF file.