The Office applications (problem exhibited in both Word and Excel) prompt to correct the invalid or missing required properties, despite the properties being correct:
'Required Properties To save to the server, correct the invalid or missing required properties.'
This problem seems to be limited to multi-line text properties, other required properties work correctly.
1) Uninstall the update(s) and block the update from automatically being installed again.
2) Install the following Office 2010 Hotfix: http://support.microsoft.com/kb/2878228/en-us