A tool from Microsoft Corporation to simplify the task of installing multiple hotfixes.
Overview A hotfix is a security patch for a Microsoft product, such as Microsoft Windows XP or Microsoft Exchange Server. Hotfixes are released whenever new vulnerabilities
and bugs are discovered in products, and most hotfixes require the system to be rebooted after they are installed. To speed up the task of installing multiple hotfixes and to reduce system downtime, Microsoft created a command-line tool called Qchain. Using this tool, you can “chain together” multiple hotfixes, installing them sequentially, and then run Qchain afterward and reboot your system only once instead of multiple times.
Qchain is included in the Resource Kits for Windows NT 4 and Windows 2000 operating systems and is also available from the Microsoft Download Center