Navigation to the webpage was canceled in chm file

Question

Hi,

I'm building a compiled help file using HTML Help Workshop 4.74.8702.  I can build the file without any problems.  However, when I open the compiled file, I get the message "Navigation to the webpage was canceled".  I cannot see any help topic that is embedded in the chm file.  I am able to add contents links to web pages and those appear fine.

If I open the compiled file on other computers, I can see the topics.  I've also tried opening other chm files on this computer (samples on how to create HTML help files) and have the same issue with them.  Other help files work just fine (ie the help files that come with Help Workshop).

Any help would be greatly appreciated.

Answer 1

Hi,

You can't view .chm files opened over a network.  I think there are workarounds for this, but you'll have to search this forum to find them.

You also can't download .chm files from a web browser and simply click Open.  Download the .chm file to your computer first, right-mouse click it in Windows Explorer and select Properties.  Then click Unblock.

- Dave

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http://davesexton.com/blog

Answer 2

As Dave mentioned above it's depending on some things, so I give some additional information. Note the difference - local help or help saved on network share.
In a connected world security updates are now a fact of life. Get used to them. Microsoft have done a mighty job of securing Windows starting with XP SP2 released in Aug 2004. Since then a string of updates have reduced the humble CHM to the status of a humble local help system. It's a shame but we need to move on.

EC-Software released a updated freeware utility to edit the registry settings. Expanding the "MaxAllowedZone" is one option to enable CHM files over the network, but you can also register individual files or folders. "HHReg" does the registry editing job and lets you comfortably register individual CHM files and/or folders. System administrators can run it in batch mode as well. HHReg is free for personal and commercial use.
Information, product link and download:
http://www.ec-software.com/products_hhreg.html

See also:
http://helpware.net/FAR/far_faq.htm#SecurityUpdates
http://helpware.net/FAR/far_faq.htm#SecurityUpdates2

and a good article:
http://www.grainge.org/pages/authoring/chm_mspatch/896358.htm

You may want to add some registry updates from the links above if you have a setup process for your Access application and your customers have no success with the first solution.

---

Ulrich Kulle - Microsoft MVP - Help - http://www.help-info.de

Answer 3

 The following article gives a good explanation of the issue and how to use the HHReg tool.

    http://www.winhelponline.com/blog/fix-cannot-view-chm-files-network-xp-2003-vista/

The Microsoft KB that describes the issue and how to work around it is:

    http://support.microsoft.com/kb/896054

--Jamey

Answer 4

Although I am not a developer, I noticed this problem after downloading a "stand-alone" program and tried to open the help file. The downloaded files were in my "downloads" folder, which was on an external USB drive - not an NAS-type arrangement. This PC is connected to another on the same  desk in front of me, via an ethernet cross-over cable, and everything is shared, so I presume the MS security step-up must have decided that it was a network drive. I used a small program called HHReg
http://www.ec-software.com/products_hhreg.html
which alters the appropriate registry entries to allow viewing.

Answer 5

I had the same problem after upgrading to IE7, All the local chm files where not working . Seems the issue is solved by unchecking the Always ask checkbox.
http://digitalpbk.com/2009/11/chm-files-navigation-webpage-was-cancelled

Answer 6

Thanks you for your help. Happy New Year :p

Answer 7

Thanks, that is good

Answer 8

There's also a good article regarding this problem on the HelpSmith website.

You can find it at:

http://www.helpsmith.com/chm-cannot-be-displayed.php

Answer 9

And I've posted a workaround for when you have downloaded a CHM from another site here; http://www.scottleckie.com/2009/05/downloaded-chm-help-file-shows-navigation-to-the-webpage-was-cancelled/

Answer 10

Hi Dave,

    Thank you very much for your instruction.

    I had the same problem with opening the chm documents which were downloaded from Internet onto my PC with the error message "Navigation to the webpage was canceled. ".

    Now I can open and read these chm documents.

    Thanks again and have a nice week,

Best regards,

 

Liangwei

Answer 11

Thanks, it solved my problem :)

Answer 12

This worked for me in Windows 7 x64. Thanks!

Answer 13

Thanx man that was gr8 help......... It workd 4 me..............

Answer 14

I was able to resolve it by opening the properties for .chm file and clicking the unblock button.

 

right click->properties on the .chm file and look for unblock button.

Answer 15

Hi,

You can't view .chm files opened over a network.  I think there are workarounds for this, but you'll have to search this forum to find them.

You also can't download .chm files from a web browser and simply click Open.  Download the .chm file to your computer first, right-mouse click it in Windows Explorer and select Properties.  Then click Unblock.

- Dave

---

http://davesexton.com/blog

It really helped me "Dave Sexton". I found the same problem as mentioned by "JStickland " in Win7 but the same files worked quite well in XP. So i was just short of unblocking in Windows 7.

Answer 16

I don't see the 'Unblock' option after right-clicking the CHM file.

Answer 17

So, as Dave mentioned earlier please download the .chm file to your computer first, right-mouse click it in Windows Explorer and select Properties.  Then click Unblock. You don't see after a right-click only.

I tried this from my homepage  http://www.help-info.de/en/Help_Info_HTMLHelp/hh.htm (search for Siungle CHM file at section HTMLHelp - Download) with Windows 7.

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Ulrich Kulle - Microsoft Help MVP - (2007-2009) - http://www.help-info.de

Answer 18

Following up - don't post to answered threads please.

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Ulrich Kulle - Microsoft Help MVP - (2007-2009) - http://www.help-info.de

Answer 19

Thanks , it worked for me now

Answer 20

Thanks for ur information dude now i can open the by using this help

Answer 21

thanks for ur information dude by using this help i can open the file once again thanks for ur precious help

Answer 22

the unblocking worked..thanx Dave . u saved ..big time!!

Answer 23

Unchecking the box fixed the problem for me! in IE9.

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GO TEAM VENTURE!!!

Answer 24

Hopefully someone can help us.  We have a similar problem that hasn't been solved.  Our users connect through terminal services to use an accounting program on a windows 2008 server r2.  If the user logs in as anything but the administrator, the help files in the accounting program give the "navigation to the website was canceled" message.  An administrator can log in and use the help files through the progam or standalone. 

If the user doesn't use terminal services, they can open the help files with their own user accounts on their local computer by accessing the network drive or using the accounting program.  Adminstrator level privileges are not needed.  

In efforts to solve this, hhreg was used to register the chm file and the help folder itself, drivers were registered individually on the server, and the file/folder permissions were set so that users could access the folder/files.  There has got to be one more step to take.  Does anyone know what it could be?  Thank you.

Answer 25

See my blog and read all info from the link inside:
http://weblog.helpinfo.eu/2010/01/19/chm-security/

You know it's depending on a lot of things in your company and net. So some more links:
http://www.grainge.org/pages/authoring/chm_mspatch/896358.htm

Don't post to answered threads please - use links to the old thread and start a new one.

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Ulrich Kulle - Microsoft Help MVP - (2007-2009) - http://www.help-info.de

Answer 26

Thanks Dave it worked for me !!

Answer 27

thank you very much , it worked!

Answer 28

>> You also can't download .chm files from a web browser and simply click Open.  Download the .chm file to your computer first, right-mouse click it in Windows Explorer and select Properties.  Then click Unblock.

That fixed it for me. What benefits does this block option (for CHM files) offer? Presumably not to prevent malicious code from running on my machine, since everything is blocked, including benign text.

Answer 29

never ending story - CHM security …

So, no benefits - security fix only. It's to prevent malicious code from running on your machine. CHM's are save only on local drives. You don't know what's inside a Compiled Help Module (CHM) coming from the web e.g. Java-Script.

JavaScript and the DOM provide the potential for malicious authors to deliver scripts to run on a client computer via the web.

Quote from Tim Greens solution (see link below)
"The outcry from outraged developers and help authors everywhere was deafening. To be honest, we never really understood the alleged security risks of CHM files on networks – to the best of our knowledge there is no record of a single malware exploit with CHMs. But Microsoft had spoken, the new law was passed and the options available to developers were extremely limited."

Developers maybe interested in following solution (see my blog):
http://weblog.helpinfo.eu/2012/05/05/making-chm-files-work-on-network-drives/

Following link may help some admin’s because well described:
http://tinyurl.com/ylkdbza

HTH

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Ulrich Kulle - Microsoft Help MVP - (2007-2009) - http://www.help-info.de

Answer 30

Hi,

You can't view .chm files opened over a network.  I think there are workarounds for this, but you'll have to search this forum to find them.

You also can't download .chm files from a web browser and simply click Open.  Download the .chm file to your computer first, right-mouse click it in Windows Explorer and select Properties.  Then click Unblock.

- Dave

---

http://davesexton.com/blog

Thanks Dave. Exactly , What I was looking for.

Cheers :)

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Kind Regards Jaber

Answer 31

This is an old thread, but I just want to thank Dave for posting and point out that Unblock still works in 2012. I had downloaded the source code for ScrewTurn Wiki, and its Help file was giving the "Navigation to the webpage was canceled" msg for every topic. Properties/Unblock on the .chm file fixed the problem, easy peasy!

Answer 32

Thanks a million Dave..that works!!... :)