For security reason, Microsoft has updated Windows® system. With the new introduction of Microsoft Security Update, you CANNOT:

- Run CHM files on network driver
- Run CHM files that downloaded with Internet Explorer directly

These affect all HTML Help files, not only those created with WinCHM!

Refer to: http://www.microsoft.com/technet/security/bulletin/ms05-026.mspx

See also:

- http://www.grainge.org/pages/authoring/chm_mspatch/896358.htm
- http://helpman.it-authoring.com/viewtopic.php?t=2870
- http://www.macromedia.com/cfusion/webforums/forum/messageview.cfm?catid=449&threadid=1015237&enterthread=y

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