A. Qchain is a tool that Microsoft has released for Windows 2000 and Windows NT 4.0 to help users install multiple hotfixes at once without having to reboot after each installation. You can download the tool from Microsoft's Web site and run the download to obtain the qchain.exe image.
To use Qchain, you simply install each hotfix (without rebooting), run Qchain to clean up the internal files (e.g., .inf files), and then reboot the system. So, for example, you could type
<path>\Q123456_w2k_sp2_x86.exe -z -m <path>\Q123321_w2k_sp2_x86.exe -z -m <path>\Q123789_w2k_sp2_x86.exe -z -m <path>\qchain.exe
The -z flag tells the hotfix not to reboot, and the –m flag tells the hotfix to execute in quiet mode.