Talk:Microsoft Compiled HTML Help

Development applications
Compiled HTML Help files can be created in other applications, such as PowerCHM. HTML Help Workshop is not the only application capable of creation of this type of document. Adraeus 04:57, July 27, 2005 (UTC)

While many HATs can create CHMs, I don't know that any can create a true CHM without using the underlying HTML Help Workshop engine - available only from Microsoft, but freely available to general users and software developers.

Year of appearance
Does anyone know when was CHM launched by MS? (the year)

For a history of Microsoft's Help engine development, see Rob Chandler's excellent site at: Helpware.net

Required DLLs
A chm file that opens in my machine, doesnt open in my colleague's. So I want to know, which are the required DLLs for CHM.

unix lib chm
In ubuntu it's libchm-bin instead of chmlib-bin. Is this only for ubuntu or...?--NESFreak 15:28, 8 October 2006 (UTC)
 * True for Debian too Optimix 00:51, 6 March 2007 (UTC)

chm on MacOSX: chmtools package not included in Fink
The chmtools are not included in Fink. I could not find an indication they ever were. The only available version of the tools are available as CVS only, and therefore cannot be installed by everyday users.

I haven't tried MacPorts yet, but search indicates a similar situation.

In short, it seems there is no way to dump .chm files on MacOSX.


 * I think the article covers pretty everything you would want to know, except for fink on Mac. I don't have a Mac available at the moment, but a search gives you right, there is no chmtools package . However, see this guide to build xchm. Cheers, --Ben T/C 09:28, 15 August 2007 (UTC)

== Correction This is not correct. chmtools have been included as unstable package since 10.3 See http://pdb.finkproject.org/pdb/package.php/chmtools Everyone that installs the developer tools and enables unstable can install chmtools. With the unofficial Todai binary distribution that is even possible without them —Preceding unsigned comment added by 77.102.37.117 (talk) 02:16, 4 January 2008 (UTC)

7Zip also decompresses CHM files
7Zip (open source) also decompresses CHM files, so it might be worth a mention in the article. 72.200.152.234 14:36, 14 March 2007 (UTC)

In Windows, the suggested method to extract all files "hh.exe -decompile extracted filename.chm" only yields a xyz.hhc file and the corresponding folder xyz (which contains all the html, graphic, css, etc files). But when I open that same CHM with 7Zip, I also get the following files and folders:

Files: &#35; IDXHDR &#35; ITBITS &#35; STRINGS &#35; SYSTEM &#35; TOPICS &#35; URLSTR &#35; URLTBL &#35; WINDOWS &#35; FIFTI~1 &#35; OBJINST

Folders: &#36; WWAssociativeLinks

&#36; WWKeywordLinks

So it is correct for the article to state: "This will decompress all files embedded in filename.chm to folder extracted." when perhaps it is better to replace 'all files' with 'all html files'? 72.200.152.234 15:14, 14 March 2007 (UTC)

Article name
I can't find a reference for the name "Compressed" help. Microsoft appears to consistently call it "Compiled" help (see this API intro, for example) or use your favorite search engine and compare hits. Please correct me if I'm wrong; otherwise, I'll move the article. Matchups 10:46, 16 March 2007 (UTC)
 * Not sure if this has changed since the above comment was made, but the official name is now Microsoft HTML Help. I will change the article name if no one objects. --Cornellier (talk) 13:27, 6 January 2013 (UTC)

Requesting reference
Quoting: "They have since announced their intentions not to develop the .CHM format further". Please add a reference for this one. —Preceding unsigned comment added by 193.190.253.145 (talk) 22:19, 30 September 2007 (UTC)

Registry modification to permit viewing of .chm files on local intranets
As a newbie contributor, I'll post this here for someone else to edit on the article page:

Recent security updates to Windows have disabled routine access to .chm files as described in: http://support.microsoft.com/kb/902225
 * NOTE: access through Internet Explorer, and access to remote/download chm files, is not 'routine access' 203.206.162.148 (talk) 06:27, 2 February 2012 (UTC)

For Wintel machines, a registry modification is described in a forum at url: http://www.nik.com.au/archives/2005/04/06/chm-help-files-error-the-page-cannot-be-displayed/

The method follows: (NOTE: This is a registry modification. Improper editing of the registry can render your system inoperable. Back up your registry before modifying it.)

Modify the ItssRestrictions registry entry to enable a specific security zone.

To modify the ItssRestrictions registry entry to enable a specific security zone, follow these steps:

1. Click Start, click Run, type regedit, and then click OK. 2. Locate and then click the following subkey: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\HTMLHelp\1.x\ItssRestrictions Note: If this registry subkey does not exist, create it as follows: Right click on the 1.x subkey, point to New, and then click Key Enter the key name: ItssRestrictions 3. Right-click the ItssRestrictions subkey, point to New, and then click DWORD Value. 4. Type MaxAllowedZone, and then press ENTER. 5. Right-click the MaxAllowedZone value, and then click Modify. 6. In the Value data box, type a number from 0 and 4, (Use 1 for local intranet) and then click OK. 7. Quit Registry Editor.

Now try to open the CHM.

the DWORD value data for “MaxAllowedZone” numbers represent the Intenet Security Zones (Internet Properties, Security Tab). The following list was taken from MS KB Article #182569: http://support.microsoft.com/kb/182569

Value Setting —————————— 0 My Computer 1 Local Intranet Zone 2 Trusted sites Zone 3 Internet Zone 4 Restricted Sites Zone

For most CHM files, the value of 1 should be enough to allow use without opening up access from/to remote CHM files in email/internet locations.

I have several e-books that are .chm files. It was an unpleasant surprise to find that I could no longer read them. The MSKB describes a file property change to "Unblock" the file, but the button on the property sheet does not appear unless the file was previously blocked. This registry change allowed me to access the files once again.

Techineer 05:29, 2 November 2007 (UTC)

Any relation to Structured storage?
Is there any relation to Structured storage? This also appears to be subfilesystem. Shinobu 09:56, 14 November 2007 (UTC)

Yes, there is a relation. IIRC IStorage interfaces can be used to read chms. A bit sluggish though. 88.159.72.252 (talk) 21:22, 24 January 2010 (UTC)

Free Pascal CHM support
Free Pascal has a (LGPL with static linking exception) CHM library with read/write support, as well as an fulltext indexing engine. The write support is "generating" chm mostly though, not adding/modifying existing CHMs. (though you could achieve that using a decompilation step followed by a compilation step). Its textmode IDE allows to browse CHMs in textmode.

It is used for the FPC documentation tools mainly. It works on all FPC supported targets (including stuff like DOS). It's not a chmlib port, but a new implementation based on the open spec.

FPC based Lazarus (software) uses this library too.

88.159.74.100 (talk) 16:18, 26 August 2009 (UTC)

Replacement/deprecation
The page says in several places that CHM is dated. I immediately believe that (since there is htmlhelp2, and MS is working on htmlhelp 3 for some next VS version), no discussion there.

However I do think that the comments that CHM is replaced in Vista by .mht etc are a bit premature, specially if I look in my Windows 7 "windows" folder, and can't find a single .mht file, and heaps of CHM files.

Probably this comment is based on helpsystems packaged with developer tools,(such as VS that also has used htmlhelp2, aka .HxS), rather than what is really what is packaged with Windows client OSes. As far as I know, CHM is still the most recent helpfile system installed by client Windows OSes. 88.159.72.252 (talk) 21:26, 24 January 2010 (UTC)

Windows hh.exe command
On Windows, a CHM file can be extracted to plain HTML with the command: ( ... )

the mentioned command fails (silently) if the .chm file has a space in the filename, maybe add that information? (87.184.192.236 (talk) 08:18, 6 July 2010 (UTC))

External links modified
Hello fellow Wikipedians,

I have just modified 2 external links on Microsoft Compiled HTML Help. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
 * Added tag to https://play.google.com/store/apps/details?id=com.kingreader.framework&feature=search_result
 * Added archive https://web.archive.org/web/20140919063747/https://play.google.com/store/apps/details?id=org.hystudio.android.chm to https://play.google.com/store/apps/details?id=org.hystudio.android.chm&feature=search_result
 * Added archive https://web.archive.org/web/20060718005033/http://www.helpware.net/htmlhelp/hh_info.htm to http://www.helpware.net/htmlhelp/hh_info.htm

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

Cheers.— InternetArchiveBot  (Report bug) 18:55, 10 June 2017 (UTC)