A yellow exclamation point appears next to the Trusted Platform Module 1.2 device in Device Manager if you install Windows Vista before you update the BIOS to a TCG-compliant version

You install Windows Vista before you update the basic input/output system (BIOS) to a Trusted Computing Group (TCG)-compliant version. If you do this, the Trusted Platform Module (TPM) 1.2 device driver (Tpm.sys) is not loaded. Additionally, a yellow exclamation point (!) appears next to the TPM 1.2 device in Device Manager.

Note The TPM 1.2 device remains in this state even after you update the BIOS to a TCG-compliant version.

This issue occurs because devices that cannot be installed during the Windows Vista installation process do not have a driver installed. These devices are marked as having failed the installation. By default, you are not prompted to install drivers for these devices.

To resolve this issue, update the BIOS to a TCG-compliant version, and then load the Tpm.sys driver. To load the Tpm.sys driver, follow these steps:

1. Open Device Manager. To do this, click Start
   Collapse this imageExpand this image

   
   , type Device Manager in the Start Search box, and then click Device Manager in the Programs list.
   
   
   Collapse this imageExpand this image

   
   If you are prompted for an administrator password or for a confirmation, type the password, or click Continue.
2. Locate the TPM 1.2 device, right-click the TPM 1.2 device, and then click Update Driver Software.
3. Click Search Automatically for updated driver software.

Note To avoid this issue, update the BIOS to a TCG-compliant version before you install Windows Vista.

The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.