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Error: 'module' Object Has No Attribute 'MODE_CCM'

Needs dev input: remove before publishing

TODO: Confirm whether MODE_CCM (SMB encryption) is still unsupported at 26.09.1 and whether a product-side fix or a narrower workaround exists, such as per-share encryption settings. Evidence: none.

Symptom​

You see the following error in the Access History of the system, or when you rescan the system from the Grant Access page:

'module' object has no attribute 'MODE_CCM'

Cause​

SMB encryption is enabled on the system.

Resolution​

IMPORTANT: To perform these troubleshooting steps, you must have the administrator role in the product, and you must be able to run PowerShell on the system.

IMPORTANT: Disabling SMB encryption removes encryption for all SMB traffic to and from the server. Data in transit, including file transfers and credentials passed over SMB, is then exposed to anyone who can capture network traffic. Disable SMB encryption only if your security policy allows it, and limit the change to the affected servers. To restore encryption, see Re-enable SMB Encryption. The error returns on a system after you re-enable encryption on it.

  1. Verify that SMB encryption is enabled. Run the following command in PowerShell:

    Get-SmbServerConfiguration | Select-Object EncryptData

  2. Disable SMB encryption on the affected servers:

    Set-SmbServerConfiguration -EncryptData $false

  3. Rescan the system from the Grant Access page to verify that the issue is resolved.

Re-enable SMB Encryption​

To restore SMB encryption on a server, run the following command in PowerShell:

Set-SmbServerConfiguration -EncryptData $true

For more information, see SMB security enhancements in the Microsoft documentation.