Policy
Encryption mode for Information Rights Management (IRM)
Microsoft Office
Policy overview
Key metadata and intent for this policy.
If you enable this policy setting, you can choose from two options for controlling the encryption mode that Excel, PowerPoint, Word, Visio, and Outlook applications use to protect content with Information Rights Management (IRM): - Electronic Codebook (ECB) – ECB mode is always used when applying IRM encryption. - Cipher Block Chaining (CBC) – CBC mode is always used when applying IRM encryption. If you disable or don't configure this policy setting: - For Microsoft 365 Apps (Version 2304 or later): Cipher Block Chaining (CBC) mode is used. - For earlier Microsoft 365 Apps and Office LTSC 2021, 2019, and 2016: Electronic Codebook (ECB) mode is used.
Registry values
How enabled and disabled states update the registry.
No explicit registry values are set for enabled or disabled states.
Policy elements
Inputs and configuration options exposed by this policy.
| Scope | Element | Type | Registry mapping | Constraints & behavior | Copy |
|---|---|---|---|---|---|
| User | IRM Encryption Mode: ID L_Encryptiontypeforirmcolon | enum | Path software\policies\microsoft\office\16.0\common\drm Value name compatibleencryption Type REG_DWORD | Options: Cipher Block Chaining (CBC) (1), Electronic Codebook (ECB) (2) |