The Outlook Add-In installer is a 'pure' MSI package. As such it will generate only very limited logging information by default. To obtain installation logs from the installer you must adopt one of the following methods.
a) Command line argument. Add the argument "/l*v <pathToLog>" to your msiexec.exe command line. This is appropriate when diagnosing a specific problem.
msiexec /i MyPackage.msi> /l*v c:\temp\msilog.log
b) Apply a generic logging policy to the computer. This will make the Windows Installer service generate verbose logs in the %TEMP% folder for all MSI operations, except where there is a local override:
Open the registry with Regedit.exe and create the following path and keys: