# Block Unknown Or Unsupported Device Access > Users will be blocked from accessing company resources when the device type is unknown or unsupported. Users will be blocked from accessing company resources when the device type is unknown or unsupported. Global Administrators are excluded as break-glass accounts, because Microsoft requires at least one excluded user, group or role on a policy that blocks all users. ## Settings this baseline controls | Setting | What it does | | -------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Policy name | Specifies a display name for the Conditional Access Policy [Learn more](https://learn.microsoft.com/en-us/azure/active-directory/conditional-access/howto-policy-unknown-unsupported-device) | | Enable policy | Specifies the state of the conditional Access Policy. Possible values are: enabled, disabled, enabledForReportingButNotEnforced. Required. [Learn more](https://learn.microsoft.com/en-us/azure/active-directory/conditional-access/howto-policy-unknown-unsupported-device) | | Included users | User IDs in scope of policy [Learn more](https://learn.microsoft.com/en-us/azure/active-directory/conditional-access/howto-policy-unknown-unsupported-device) | | Included roles | Role IDs in scope of policy [Learn more](https://learn.microsoft.com/en-us/azure/active-directory/conditional-access/howto-policy-unknown-unsupported-device) | | Included groups | Group IDs in scope of policy [Learn more](https://learn.microsoft.com/en-us/azure/active-directory/conditional-access/howto-policy-unknown-unsupported-device) | | Included guest types | Guest or external user types in scope of policy [Learn more](https://learn.microsoft.com/en-us/azure/active-directory/conditional-access/howto-policy-unknown-unsupported-device) | | Excluded users | User IDs excluded from scope of policy [Learn more](https://learn.microsoft.com/en-us/azure/active-directory/conditional-access/howto-policy-unknown-unsupported-device) | | Excluded roles | Role IDs excluded from scope of policy [Learn more](https://learn.microsoft.com/en-us/azure/active-directory/conditional-access/howto-policy-unknown-unsupported-device) | **5 more settings** | Setting | What it does | | ------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Excluded groups | Group IDs excluded from scope of policy [Learn more](https://learn.microsoft.com/en-us/azure/active-directory/conditional-access/howto-policy-unknown-unsupported-device) | | Excluded guest types | Guest or external user types excluded from scope of policy [Learn more](https://learn.microsoft.com/en-us/azure/active-directory/conditional-access/howto-policy-unknown-unsupported-device) | | Grant controls | List of values of built-in controls required by the policy. Possible values: block, mfa, compliantDevice, domainJoinedDevice, approvedApplication, compliantApplication, passwordChange, unknownFutureValue [Learn more](https://learn.microsoft.com/en-us/azure/active-directory/conditional-access/howto-policy-unknown-unsupported-device) | | Included device platforms | Possible values are: android, iOS, windows, windowsPhone, macOS, linux, all, unknownFutureValue. [Learn more](https://learn.microsoft.com/en-us/azure/active-directory/conditional-access/howto-policy-unknown-unsupported-device) | | Excluded device platforms | Possible values are: android, iOS, windows, windowsPhone, macOS, linux, all, unknownFutureValue. [Learn more](https://learn.microsoft.com/en-us/azure/active-directory/conditional-access/howto-policy-unknown-unsupported-device) | [Adding a baseline](https://docs.octiga.io/baselines/adding-a-baseline/) — Add, configure or remove a single baseline on a tenant, a user or a group, without deploying a whole scheme. ## Configure it Add this baseline when access should be refused from any device platform your organisation doesn't use, closing the gap an unrecognised or spoofed client could otherwise slip through. 1. Add the baseline to the tenant directly (see [Adding a baseline](https://docs.octiga.io/baselines/adding-a-baseline/)), or carry it in a scheme you deploy to every tenant you manage (see [Deploying a scheme](https://docs.octiga.io/baselines/deploying-a-scheme/)). 2. Leave **Included users** covering everyone, and use **Excluded users** or **Excluded groups** for your organisation's break-glass accounts. 3. Leave **Included device platforms** set to any device, and set **Excluded device platforms** to Android, iOS, Windows and macOS, or whichever of those your organisation uses. The baseline blocks every platform you don't exclude. 4. Leave **Grant controls** set to block. 5. **Save.** Turn on **Auto-remediation** if you want Octiga to reapply the policy whenever it's changed in Microsoft 365. > **Caution:** Device platform is read from the client's own user agent string, which can be altered, so pair this with a device-compliance or app-protection baseline rather than relying on it alone. Check that the platforms you exclude cover everything your organisation uses: Linux and any other platform outside that list is blocked outright. > **Licence: Entra ID P1 or P2:** This baseline needs Entra ID P1 or P2 on the tenant. Without it, Octiga excludes the baseline rather than reporting it as deviated — see [Licence requirements](https://docs.octiga.io/reference/licence-requirements/). ## Check it worked After the next sync, this baseline shows **Passing** once a policy with `state` set to `enabled`, the excluded-platforms condition, and the block grant control exists in Microsoft Entra. You can confirm it in the Microsoft Entra admin centre under **Entra ID > Conditional Access > Policies**. Users on a supported platform notice nothing; anyone signing in from an unrecognised one is refused access. ## Standards this addresses ### CIS - **v8 4.1** — CIS Controls v8 Safeguard 4.1 - **v8 6.4** — CIS Controls v8 Safeguard 6.4 ### NIST - **PR.AC-7** — NIST CSF 2.0 PR.AC-7 - **SC-7** — NIST SP 800-53 SC-7 - **CM-7** — NIST SP 800-53 CM-7 ### ISO 27001 - **A.8.22** — ISO/IEC 27001:2022 Annex A.8.22 **Doing this for every tenant?** Step through the deploy wizard to apply a scheme to a tenant, groups or users, and see what Managed and Direct do at deploy time. [Deploying a scheme](https://docs.octiga.io/baselines/deploying-a-scheme/)