@Franck Marteaux Thanks for reaching out and apologies for delay on this.
To disable IRM GUI for the desired Office application set the following registry values. Note, these may be used with the Office group policy templates or via a group policy pushing out registry preferences. When doing the manual preferences note that the values are written to the Policies key under Software.
HKCU\Software\Policies\Microsoft\Office\14.0\Word\DisabledCmdBarItemsList
HKCU\Software\Policies\Microsoft\Office\14.0\Excel\DisabledCmdBarItemsList
HKCU\Software\Policies\Microsoft\Office\14.0\PowerPoint\DisabledCmdBarItemsList
Value Name: TCID1
Value Type: REG_SZ
Value Data: 7990
TCID 7990 disables the items on the flyout menu of File / Info / Protect Document / Restrict Access option.
You can read more at https://social.technet.microsoft.com/wiki/contents/articles/9755.ad-rms-how-to-disable-irm-functionality-for-some-office-applications.aspx
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