Symptoms
After you install the August 2014 update rollup for Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2 (2975719) on a computer that is running Windows 8.1, universal serial bus (USB)-composited Mobile Broadband Interface Model (MBIM) devices may not display the correct device class.
Cause
After you install update 2975719, two registry entries are removed that are required to complete the installation of USB-composited MBIM devices.
Workaround
Important
Follow the steps in this section carefully. Serious problems might occur if you modify the registry incorrectly. Before you modify it, back up the registry for restoration in case problems occur.
To work around this issue, add the missing registry entries manually, and then rescan the device to complete the device installation. To do this, follow these steps:
-
Open Registry Editor, and then locate to the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\DriverDatabase\DriverPackages\wmbclass_wmc_union.inf_xxx\Configurations\CCGPDriverInstallIADxxx.NT\Device
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Add the following registry entries under the registry subkey, and make sure that the administrator is the owner of the registry subkey:
Value name: OriginalConfigurationValue
Data type: REG_DWORD
Value data: 1
Value name: AltConfigurationValue
Data type: REG_DWORD
Value data: 0 -
Change the "Owner" permission back to the permission that was previously assigned.
-
Reinstall the device through Device Manager.
More Information
To take ownership of a registry key in Windows 8.1, follow these steps:
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In Registry Editor, select the registry key that you want to take ownership of, right-click it, and then select the Permissions option.
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Click Advanced, and then click the Change link next to Owner.
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Select the user account through the Advanced button. Or type your user account in the Enter the object name to select text area, and then click OK.
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.