Helpfile Word Lists May Be Rebuilt After Daylight Savings Change

• Microsoft Windows NT Workstation version 4.0
• Microsoft Windows NT Server version 4.0

SYMPTOMS

The first time you select the Index or Find tab in a Helpfile Help Topics dialog, the Help system prompts you to build an associated word list. Once the word list is built, it should not need rebuilding unless the Helpfile has been modified.

However, if the Helpfile resides on an NTFS partition, and your computer is set to automatically adjust for Daylight Savings Time (DST), you may be prompted to rebuild the word lists following a change to or from DST, even though the underlying Helpfile has not been modified. For example, if you build the word lists in August (in DST), and revisit the Index or Find tabs in November (outside of DST), you will be prompted to rebuild the word lists.

Word lists for Helpfiles that reside on FAT partitions are not affected by this problem.

CAUSE

File timestamps on NTFS file systems are stored as UTC (GMT) times. These times are adjusted to Local Time by applying the DST bias, for display purposes, as and when required.

When the Help system builds word lists, it records the timestamp of the Helpfile from which the lists were built in the word list files themselves, and uses this time to detect changes to the Helpfile, when deciding whether or not the word lists need to be rebuilt.

The Help system was incorrectly comparing the timestamp Local Time format, which is incorrect -- it should have been comparing the timestamps in UTC format, as these are invariant with respect to DST changes.

RESOLUTION

To work around the problem, rebuild the Helpfile word lists following each Daylight Savings Time change.

Alternatively, apply the related hotfix and rebuild the word lists once -- word lists built using the hotfix are not affected by DST changes.

STATUS

Microsoft has confirmed this to be a problem in Windows NT version 4.0. This problem was corrected in the latest Microsoft Windows NT 4.0 U.S. Service Pack. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

   S E R V P A C K