This is due to Outlook Disabling your toolbar. To re-enable your toolbar please follow the steps below:
* If you are using Outlook 2007:
-Click on the “Help” Toolbar.
-Click on “Disabled Items”
-Select EmailTags and click on “Enable”
-Click on “Close” once you’re done.
* If you are using Outlook 2010:
-File-> section Options-> section Add-Ins
-At the "Manage" dropdown list at the bottom select which type of add-ins you would like to enable/disable
-Press "Go…" and make the changes
-For some add-ins you'll need to restart Outlook for changes to take effect.