You'd want to make at least three changes:
1) The registry value that controls the default stationery for the user is
in the HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Common\MailSettings
key in an expandable string value named NewStationery. Set the value to the
name of the HTML file, without the .htm tag. In other words, if the name of
the stationery file is "Company Letterhead.htm," the value for NewStationery
would be "Company Letterhead." If you put in the name of a stationery file
that is not in the user's Stationery folder, e.g. "dummy," Outlook will use
the user's default fonts, and the user will not be able to invoke any
default stationery.
I haven't tried this setting as a policy setting yet, but I suspect it will
work.
2) In the same key, you should also create a string value named NewTheme to
a dummy value to block the user from using Word's Tools | Options | E-mail
Options dialog to set a theme.
3) You would also want to disable the Actions | New Mail Message Using |
More Stationery command using a group policy object and the "Disable command
bar buttons and menu items" policy setting. The ID for that command is
5611.
However, these measures will be only partially effective in enforcing the
use of particular stationery. The user could always edit the raw .htm file
in the Signatures folder or replace it with one with the same name. A
WordMail user can also change the background and fonts by using the Format |
Theme command, unless you block that menu choice for all Word documents.
Furthermore, if the user has previously used stationery, the most recently
used stationery choices will be available in the Actions | New Message Using
menu and cannot be cleared. I haven't found the MRU list yet.
