Service Pack 6 Details
If you read the news at the Windows NT Magazine site on Friday, you know that Microsoft released Service Pack 6 (SP6) for public download on the Service Pack Web site. You can upgrade your system online, download the 34.5MB update file, or order the CD-ROM from Microsoft. The file sp6i386.exe expands to 67MB of files, and you need 120MB of free space for the expanded files and the uninstall directory. As I discussed in an earlier column, SP6 doesn't include the post-SP6 RAS hotfix, so you need to install the hotfix either before or after you apply SP6 (you don’t have to apply it twice). I downloaded and installed SP6 with no problem, but I’ve only been running the new version for a few days—it’s too early to tell if there are showstopper issues waiting in the wings.

The CD-ROM version of SP6 contains more updates than the download version, including improvements to Internet Explorer (IE) 5.0, the Security Configuration Editor (SCE), Distributed Component Object Model (DCOM), Winsock, Microsoft Message Queue Server (MSMQ) files for Windows 9x, additional print drivers, files to install RRAS in unattended Setup mode, and updates to Certificate Server and Internet Authentication Service (IAS). You can order the CD-ROM at the download site.

SP6 encryption versions. Be sure you download the correct encryption version of SP6, because if you apply the 56-bit encrypted service pack to a 128-bit encrypted OS, you can compromise either the security or the exportability of your system. You can use two techniques to determine the encryption level of your OS:

  • Look at the properties of the \WINNT\system32\schannel.dll file. If the Description field on the Version tab says "US and Canada," you're running the 128-bit version of NT. If the Description says "Export Version," you're running 56-bit encryption.
  • If the file rsaenh.dll appears in the system root, you're running the 128-bit version.

Microsoft Exchange reindexing. The SP6 README file cautions that when you install SP6 on a system running Exchange Server, Exchange Server might initiate a full index recalculation. If Exchange Server does start calculating a new index, be sure to let it complete—if you interrupt the index operation, Exchange Server might corrupt the database it's processing. When I upgraded my Exchange Server system, there was a long pause after I logged on and before the desktop appeared, and I found several sets of Exchange recalculation events in the Application event log (Category of Table/Column and Event IDs 174 and 175). These log entries indicate that Exchange Server cleaned up the Public and Private databases, as well as the Directory database. If your Exchange Server has a large database, this cleanup operation can add from 15 minutes to an hour or more to your upgrade time, as well as slow mail delivery, so be sure you plan ahead.

Option Pack updates. The SP6 README file indicates that the upgrade includes Windows NT 4.0 Option Pack fixes, but the description of the updates that the service pack will apply isn't clear. I couldn't determine whether you get Internet Information Server (IIS) 4.0 fixes only, or whether SP6 updates all Option Pack components. We can only hope that the SP6 test team verified that the updates work with all versions of all components that ship in this collection. As with previous service packs, you might see a message telling you that Microsoft hasn't tested the Option Pack updates on SP4, and you can safely click Yes to proceed with the update.

The SP6 IIS 4.0 update doesn't correctly set script execute permission for the Microsoft Proxy Server Web Administration Tool. If this Web Administration Tool doesn't start after you install SP6, you can correct the problem by adding Script permission to the Virtual Directoy in PrxAdmin.

Internet Explorer 5.0. SP6 lets you install IE 5.0 without creating its desktop icon or making the file associations that establish IE as the default browser. Installations that don’t allow Internet browsing will appreciate this improvement. IE 5.0 updates are available only on the SP6 CD-ROM, and you must run the IE 5.0 update from the command line to disable the desktop icon and IE’s status as the default browser.

3Com EtherLink 905B. SP6 automatically replaces earlier versions of the 905B driver. If you have problems with your network adapter card, you might need to reinstall the earlier version. Check the version of your driver and make sure you have a backup copy before you apply SP6.

Windows 2000. Here are three tips for Windows 2000 (Win2K) and NT 4.0 coexistence. First, you must give a unique computer name to each instance of the OS. Second, if you install NT 4.0 on a system already running Win2K, you need to install it with the new version of winnt32.exe from the Support directory of the SP6 CD-ROM. If you try to install NT 4.0 with the winnt32.exe code from the download version, the NT 4.0 system root might reboot continually. Third, SP6 includes a version of NTFS that's compatible with the Win2K file system, which means your NT 4.0 system can read NTFS version 5 volumes. However, the updated ntfs.sys doesn't allow an NT 4.0 system to access mount points, the encrypting file system, or disk quotas.

Desktop Icon Corruption Follow Up
Many readers report corrupt desktop icons, and although many experience the problem specifically with the TweakUI utility, others see corrupt icons as often as every couple of days. Microsoft Support Online article Q199152 documents icon problems that occur with TweakUI and IE 4.0. The article recommends that you remove TweakUI, increase and then decrease the icon size by 1, delete ShellIconCache, then log off and back on. Apparently, TweakUI contains a repair utility to correct icon problems, but readers claim the utility doesn't prevent icon corruption from reoccurring (I don't run this utility, so I can’t verify this). Another reader suggested that Win9x icon corruption might be related to certain versions of the IE 4.0 desktop, specifically IE 4.0's rebuild of the Start menu. I’m not sure how many desktop update versions exist for IE 4.0, but this observation sounds right on the mark to me.