Applying recent Windows updates appears to prevent HTML help files from displaying correctly when accessed remotely (UNC & network drive)


  • Hi,

    This appears to be an issue since applying the recent Windows updates as per below:

    Windows Server 2016: KB4103720 / KB5103723

    Windows Server 2012 R2 KB 4103725 

    The contents display as expected when opening them as a local resource, but when opening from a remote local e.g. UNC path or network drive, the content is not displayed and is replaced with:

    This page can’t be displayed
    Make sure the web address //ieframe.dll/dnserrordiagoff.htm# is correct 
    Look for the page with your search engine
    Refresh the page in a few minutes

    The CHM files aren't blocked, and were working until the updates were applied.

    All previous known fixes to resolve similar issues with display of HTML help files (MaxAllowedZone and UrlAllowList) have been applied to no avail.

    After uninstalling update KB4103720 (on a test Windows 2016 server) and a reboot, with no other changes made, HTML help works again as a network resource afterwards.

    I haven't been able to confirm with reference the other 2 KB updates as these are production servers for the company I work for.

    • แก้ไขโดย Dr.Beaker 18 พฤษภาคม 2561 21:39 Formatting
    18 พฤษภาคม 2561 15:20


  • Hi,
    Based on the complexity and the specific situation, we need do more researches. If we have any updates or any thoughts about this issue, we will keep you posted as soon as possible. Your kind understanding is appreciated. If you have further information during this period, you could post it on the forum, which help us understand and analyze this issue comprehensively.
    Sorry for the inconvenience and thank you for your understanding and patience.
    Best Regards,


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    21 พฤษภาคม 2561 2:57