I recently heard about a Microsoft resource kit utility called QChain but can't seem to find it anywhere. What is this utility, and where do I get it?

QChain, which the Microsoft article "Use QChain.exe to Install Multiple Hotfixes with Only One Reboot" (http://support.microsoft.com/support/kb/articles/q296/8/61.asp) describes, is a new utility for Windows 2000 and Windows NT 4.0. The tool lets you safely install multiple hotfixes during the same session (i.e., without requiring a reboot after each hotfix). You can also use QChain to install hotfixes at the same time as a service pack (e.g., Service Pack 2—SP2—plus a number of post-SP2 hotfixes).

To use QChain, you first install the service pack and/or the hotfixes with the -z switch (to prevent reboot after installation) and the -m switch (for quiet installation mode—note that for Windows XP, you use the /Q switch instead of the -m switch). Then you run QChain.

Without QChain, installing multiple hotfixes (with or without a service pack) without a reboot in between isn't advisable because of the way systems update files that are locked or in use during a hotfix update. The system places such files in a special Pending File Rename queue, then replaces the files in that queue during the next reboot. However, more than one hotfix might need to update the same Pending File Rename file. When you install multiple hotfixes without rebooting between updates and more than one update affects the same pending file, you can end up with an older, incorrect version of the file after you finally reboot. QChain ensures the installation of the latest version of all files affected by multiple hotfixes.

Although QChain is technically a resource kit utility, it was released after the most recent supplements to both the Microsoft Windows 2000 Server Resource Kit and the Microsoft Windows NT Server 4.0 Resource Kit. At the time of this writing, you can obtain the tool only through a download (available at http://www.microsoft.com/downloads/release.asp?releaseid=29821).

If you're particularly interested in hotfix management, I suggest you use another free Microsoft tool: Hfnetchk, which the Microsoft article "Microsoft Network Security Hotfix Checker (Hfnetchk.exe) Tool is Available" (http://support.microsoft.com/support/kb/articles/q303/2/15.asp) discusses. Hfnetchk verifies and reports a machine's currently installed hotfixes so that you can be sure your system is properly updated. Verifying this information is especially important for machines that might have had multiple hotfixes improperly installed as I described earlier. You can download Hfnetchk at http://www.microsoft.com/downloads/release.asp?releaseid=31154.

If you're looking for a good third-party hotfix and update management solution, look into such products as St. Bernard Software's UpdateEXPERT (formerly SPQuery) and Gravity Storm Software's Service Pack Manager. (For a review of these tools, see Joshua Orrison, "Ahead of the Service Pack," November 2000.) These tools report, install, and manage local and remote OS hotfixes. Some tools can also manage updates for other applications, such as Microsoft IIS, SQL Server, Exchange Server, Internet Explorer (IE), and NetMeeting.