Calling anything crash-proof is asking for trouble! Despite Windows NT 3.51's reputation for stability and crash-resistance, it is far from perfect. NT users are continually finding bugs and reporting them. But they don't want to wait for the next release of NT to have the bugs fixed, so Microsoft provides Service Packs--interim updates that fix reported bugs and provide some enhancements.
At press time, the current release for Windows NT 3.51 was Service Pack 3. Service Pack releases are cumulative, so Service Pack 3 also contains all the fixes that were in Service Pack 1 and 2.
What, Where, When, How
Although there's only one Service Pack for both Windows NT Workstation and Server, there are different versions for the Intel, PowerPC, MIPS, and Alpha platforms. And the Service Pack for one CPU platform doesn't necessarily fix the same bugs that the Service Packs for the others fix.
To find out whether the most recent Service Pack fixes a particular bug, you need to read its README file. This file contains a complete listing of the bugs fixed. Service Packs can be found via File Transfer Protocol (FTP) at ftp.microsoft.com\bussys\winnt\winntpublic\fixes\nt351\ussp3 or on the Web in the drop zone at http://www.winntmag.com. The README file also contains instructions for installation and for when you might need to reapply the Service Pack.
Installing a Service Pack is easy. After you download it, run the executable file to extract it. Then run UPDATE.EXE, and follow the instructions on the screen. Service Pack 3 is only for NT 3.51 and won't run on any other version. (I tried to install it on my laptop, which is running NT 3.51 with the Explorer GUI, and it wouldn't install because the new shell's version number is 4.0.)
Although the Service Pack is available at no charge, you may not want to install one unless it solves a particular problem you're having. Service Packs can cause more problems than they fix, so be careful. Once one is installed, the only way to uninstall it is to reinstall NT.
You may want to wait until other users have tested a new Service Pack before you install it. You can watch Microsoft's Knowledge Base, TechNet, and CompuServe to find out if it's safe before you put it on your system.
More Than One
Service Packs are also available for Microsoft BackOffice products. Currently, they exist for Microsoft SQL Server 6.0 and Microsoft Systems Management Server (SMS) 1.1. These Service Packs can be found via FTP at ftp.microsoft.com in the \bussys\sql_odbc\sql-public and the \bussys\winnt\sms-public\fixes directories, respectively, or in the drop zone at http://www.winntmag.com.