Reset WORD

1. Close Word application
2. Delete Normal.DOTM and BuildingBlocks.DOTX: these files are rebuilt automatically next time Word is started. Normal.DOTM and BuildingBlocks.DOTX usually reside in C:\Users\Username\AppData\Roaming\Microsoft\Templates (Username is your Windows profile name);The default NORMAL.DOTM file used for new profiles can be stored in C:\Users\Default\AppData\Roaming\Microsoft\Templates.
3. Use regedit to delete HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Word\Data key: it will be rebuilt automatically next time Word is started.

Source: http://www.nullalo.com/en/how-to-reset-word-settings-without-reinstalling/