The ACPI\MSFT0101 device is part of Intel's Platform Trust Technology (PTT), which provides Trusted Platform Module (TPM) 2.0 functionality. It is a chipset component rather than a peripheral device. It handles secure storage of credentials and cryptographic key management.
To resolve this "Unknown Device," you typically need a specific Microsoft update rather than a traditional driver file.
Boot back into Windows 7. The unknown device error will now be gone. Method 3: Install Intel Chipset Device Software
The only real impact is that you cannot use (drive encryption) with a TPM 2.0 chip under Windows 7, and some security software that relies on the TPM may not function. Acpi Msft0101 Driver Windows 7
: Look for KB2920188 . While Microsoft's direct download links are often retired, you can frequently find the standalone installer on manufacturer support pages like the HP Support Community or Dell Support .
: Windows 7 natively supports TPM 1.2. It does not include the built-in cryptographic architecture required to recognize or communicate with TPM 2.0 devices.
Steps for this method:
The only working solution is to use the on Windows 7.
IFX TPM 2.0 driver for Windows 7 or Infineon TPM 2.0 driver package .
Upon reboot, Windows 7 will recognize the ACPI\MSFT0101 device, and it will appear under the "Security Devices" section in Device Manager. Method 2: Change TPM Settings in BIOS/UEFI The ACPI\MSFT0101 device is part of Intel's Platform
Since Windows 7 does not include this driver out of the box, you must manually install it. Method 1: Installing the Microsoft Hotfix (Recommended)
Disable the TPM chip entirely by selecting TPM Status -> Disabled or Security Chip -> Disabled .
The ACPI\MSFT0101 hardware ID is one of the most common sources of Device Manager errors for users running Windows 7 on modern computer hardware. When this error occurs, a yellow exclamation mark appears next to an "Unknown Device," causing system instability, slow boot times, or peripheral malfunctions. To resolve this "Unknown Device," you typically need
Power on the system and repeatedly press the setup key (typically , F10 , F12 , or Del ) to enter the BIOS/UEFI menu. Switch to Advanced Mode or the Security tab.