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Run the regedit command from the command line.Solution: Modify the ItssRestrictions registry entry to enable a specific security zone. If the associated security zone is restricted, then CHM files won’t be displayed as well. on the network drive or on a remote server, you may also get in trouble. The CHM file is in the restricted Internet zone When a CHM file that you are trying to access is stored remotely, e.g. Once the CHM file has been unblocked, the Unblock button disappears. Click on the Unblock button immediately below the Advanced button on the General page. Solution: Run Windows Explorer, right-click on the CHM file, and select Properties from the popup menu. Additional information is available here. Also avoid using ‘?’, ‘&’, and ‘+’ characters in directory names.Ī security update for Windows XP® may block access to CHM files Windows XP® security update blocks active content in CHM files to protect your system security. Solution: Remove the ‘#’ (hash) character from the directory name. Your CHM files are stored in the folder with ‘#’ (hash) character in the path Many C# developers discovered that their documentation and e-books in CHM format cannot be read because they were storing their CHM files in the directories like ‘C:\E-books\C#\’ The hash character signifies an anchor in HTML so the CHM viewer fails to resolve the path properly and to retrieve the content. Solution: Run “regsvr32 hhctrl.ocx” command from the command line to register the library in the system. You must copy the CHM to a local path in order to view it.The HTML Help (CHM file) viewer component is not properly registered on your PC The system file \system32\hhctrl.ocx may get missing, corrupted, or unregistered. Security restrictions in Windows prevent you from viewing content in a CHM file on a network path. chm stored in a path that contains a # will render the. Cause 2 : CHM stored in a folder containing the # character To fix, right click on the CHM in windows explorer, select the Properties menu item and on the displayed dialog click the Unblock button.
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If you download a CHM from the internet or an untrusted network location, Windows may add a "Blocked" flag to the file that prevents you from viewing the content.
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If you see a "Navigation to the webpage was canceled" message when you open a CHM, most commonly when you download or copy a CHM file from the Internet or a network path, there are a couple of likely causes: Cause 1 : CHM is marked as "Blocked"
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