My Outlook plug-in deactivates every time I start Outlook

This is a general add-in issue in Outlook and can be resolved by performing the following:

Step 1: Exit Outlook and uninstall the MeetingBooster plug-in from Windows Control Panel -> Programs -> Programs and Features -> Uninstall

Remove MeetingBooster Outlook Add-in

Step 2: Open your Windows registry (run regedit.exe from Command Prompt)

Run Regedit.exe from Command Prompt

Step 3: Locate the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\Resiliency

(Replace 15.0 with your actual Outlook version: 15.0 means Outlook 2013, 14.0 means Outlook 2010, 13.0 means Outlook 2007, etc)

Step 4: Remove the REG_BINARY keys found in DisabledItems and CrashingAddinList:

remove REG_BINARY keys

Step 4: Delete the registry keys in:
HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\Addins\MeetingBosterOutlookPlugin

Step 5: Re-install the MeetingBooster plug-in

Step 6: Restart Outlook