Here are my notes on that (I'm running Vista 64 Ultimate): RUNNING MULTIPLE INSTANCES OF OUTLOOK Download and install "ExtraOutlook.exe" from: http://www.ham

Here are my notes on that (I'm running Vista 64 Ultimate): RUNNING MULTIPLE INSTANCES OF OUTLOOK Download and install "ExtraOutlook.exe" from: http://www.hammerofgod.com/download/ExtraOutlook.zip http://www.hammerofgod.com/download/ExtraOutlook.zip Copy the executable to the folder where outlook lives. In the current case that means: C:\Program Files (x86)\Microsoft Office\Office12\ Create a profile for each separate instance of Outlook we want to run: To create and manage profiles in Vista 64 go to Control Panel > View 32-bit Control Panel Items > Mail > Show Profiles Create or modify the Outlook shortcut on the desktop to access the desired profile: Profile 1: "C:\Program Files (x86)\Microsoft Office\Office12\ExtraOutlook.exe" "C:\Program Files (x86)\Microsoft Office\Office12\OUTLOOK.EXE" /profile "Profile 1" Make a duplicate copy and then... Profile 2: "C:\Program Files (x86)\Microsoft Office\Office12\ExtraOutlook.exe" "C:\Program Files (x86)\Microsoft Office\Office12\OUTLOOK.EXE" /profile "Profile 2" Now two instances of Outlook can be opened and each is independently accessing the corresponding profile's data. I go through the extra effort of assigning a different icon to each account and placing them on the quick-launch toolbar. I've been doing this for about two years and it works great. No issues whatsoever. I can't believe MS doesn't implement MDI in Outlook so that one can do this using tabs and a single instance.