Drivers fail to install if Telnet Server is started under Local System Account

Applies to: Windows 7 EnterpriseWindows 7 Enterprise NWindows 7 Home Basic More

Symptoms


Consider the following scenario:
  • On a Windows 7 or Windows Server 2008 R2 computer, you install the Telnet Server service.
  • In the Services Microsoft Management Console (MMC), you configure the Telnet Server service to start manually or automatically.
  • Additionally, in the Services MMC, you modify the Telnet Server service to log on using the Local System account, and you do not select the checkbox to "Allow service to interact with desktop."
In this scenario, you may find that after the Telnet Server service has been started, Plug and Play device installations are no longer successful. If you try to install a new device, you get an error stating "Device Driver software was not successfully installed." The new device is displayed in Device Manager as an "Unknown Device" and shows an error.


Cause


For security reasons, during initialization, the Telnet Server service makes some permission changes to the window station it is running in. If you configure the Telnet Server service to run using the Local System account without the ability to interact with the desktop, it gets started under a different window station. This may cause problems for other processes which also run under the Local System account and do not interact with the desktop. One such process is the driver install process, which is used during installation of a new device driver.

Resolution


To work around this problem, do not change the Telnet Server service to run under the Local System account. It is recommended that you leave the Telnet Server service running under its default "Local Service" account.