Microsoft has released Service Packs (SP) SP1, SP2, SP3, SP4, SP5, SP6, and SP6a for NT 4.0. More to come because Windows NT will be the workhorse for several years until Windows 2000 becomes the defacto standard. Service Packs have bug fixes for know problems, enhancements to NT, and each has it's own new bugs to be discovered and hopefully to be fixed in the next SP. Service Packs are cumulative. SP6 has all the known bug fixes for SP1-5 with its own new fixes. You do not need to install anything but the last SP to get the benefit of all previous versions.

Should you install SPs? SP3 is the security SP. SP4-SP6 has Y2K fixes. Microsoft's official position is that one needs not to install a SP unless it fixes a problem you are having. This is extremely good advice. If it ain't broke, don't fix it. You need to install SP3 at least. Lots of software will not install unless Windows NT is running at least at SP3. A good conservative approach which I follow is to install the latest SP approximately 6 months after its initial release. This gives Microsoft plenty of time to fix any fatal or common problems with the service pack. If you are very conservative, I would recommend installing SP6 and staying at the level until or if forced to upgrade because of a problem fixed by a new SP on your system.

What about hotfixes? Microsoft releases hot-fixes for severe bugs so that NT can be patched until the bug fix is implemented in the next SP. Unless you have a severe problem which the hot-fix controls, don't download and install hot-fixes. By their nature, they are quick and dirty code changes which are poorly tested. The bug fixes in SPs undergo a much more rigourous testing (regression testing). Wait for the next SP if at all possible.

What about security patches? Microsoft releases security patches for Internet Explorer IE at an amazing rate. Somewhat less for Outlook. In these cases one is balancing the risk of applying a poorly tested security patch to a stable but possibly insecure platform. I would recommend applying security patches for the products you use as they come out. At least for IE and Outlook.

Check How to Obtain the Latest Windows NT 4.0 Service Pack for updated information on latest service packs for Windows NT and Windows NT Terminal Server Edition. Also list bugs fixed in each patch.

SPCheck is a free command line utility release by Altus Network Solutions that can be used to check the service pack and hot fixes on any NT Workstation or Server (assuming you have administrative privileges on the machine). SPCheck v.1.4 checks multiple machines and generates a web page or a comma-delimited text file that you can easily import in a spreadsheet or database program.

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