Using Windows 7 & whenever exit Outlook, there's a message prompt,
"MS Words has stopped working. Windows is checking for solution" or "The file normal already exist. Do you want to replace the existing file".
This could be due to two version of MS Office installed, or the either one version was uninstall, by left traces in the registry.
Found a solution after hours of googling. Uninstall MS Office using FixIt tool from http://support.microsoft.com/kb/290301
Delete files in Template folder located at User\userprofile\appdata\roaming\microsoft
Remove all temp file found by issuing this command %temp%