DTOO190 - Office System - The encryption type for password protected Office 97 thru Office 2003 must be set.
If unencrypted files are intercepted, sensitive information in the files can be compromised. To protect information confidentiality, Microsoft Office application files can be encrypted and password protected. Only users who know the correct password will be able to decrypt such files.
Set the policy value for User Configuration -> Administrative Templates -> Microsoft Office 2010 -> Security Settings 'Encryption type for password protected Office 97-2003 files' to 'Enabled (Microsoft Enhanced RSA and AES Cryptographic Provider,AES 256,256)'.