I have recently upgraded to Windows 8 Release preview and realized that there was some issue with my Outlook 2010 when loading up. After some searching online, I’ve consolidated some of the list of fix for Outlook being stuck on the “loading profile” splash screen.
These fix are sorted accordingly from least amount of effort, to most amount of effort (which might require you to rebuild and download your mails)
1. Close Microsoft Lync or Microsoft Communicator before launching Outlook
2. Disable or kill “agent.exe” process from task manager after launching Outlook (agent.exe have been reported to appear on some machines, and killing this task solved the problem for many folks)
3. Launch in safe mode by holding to the Ctrl key and double clicking on Outlook icon
4. Reset the navigation pane of Outlook. Press WinKey+R. Type outlook.exe /resetnavpane
(These steps onwards will require you to rebuild your pst/ost files and re-download your emails. Proceed with caution)
5. Destroy all traces of your profile.
i. Goto Control Panel> Mail (32 Bit)> Show Profile> Delete all Profile
ii. Delete all ost/pst from C:Users<insert your user name here>AppDataLocalMicrosoftOutlook
iii. Start regedit and delete Profiles from HKEY_CURRENT_USER/Software/Microsoft/Windows NT/CurrentVersion/Windows Messaging Subsystem/
iv. Now start Outlook and enter name for your new profile. “Outlook” would be fine.