Filename Extensions
If you are seeking information about file extensions, then you are in the right place at right time.

Details of extension .hm

1 extension(s) and 0 alias(es) in our database

Below, you can find answers to the following questions:

  • What is the .hm file?
  • Which program can create the .hm file?
  • Where can you find a description of the .hm format?
  • What can convert .hm files to a different format?
  • Which MIME-type is associated with the .hm extension?
WinHelp Context ID .hm file icon

WinHelp Context ID

HM file is a Windows Help Context ID. Microsoft WinHelp is a proprietary format for online help files that can be displayed by the Microsoft Help browser winhelp.exe or winhlp32.exe. The file format is based on Rich Text Format (RTF). It remained a popular Help platform from Windows 3.0 platform through Windows XP. WinHelp was removed in Windows Vista to discourage software developers from using the obsolete format and encourage use of newer help formats.
Category: Development files
Application: Visual Studio
Program name: -
Mime-type: application/octet-stream
Magic bytes (HEX): -
Magic string (ASCII): -
Related extensions:
Windows Help File
HTML Help Project
Windows Help Project
HTML Help Header File
Windows Help Related Data

Other types of files may also use the .hm file extension. If you have helpful information about .hm extension, write to us!

Is it possible that the filename extension is misspelled?

We found the following similar extensions in our database:

X Bitmap Image
Autologic Bitmap Image
HTML Help Header File
Habanero-Java Source Code
ASCA GIS Housekeeping Data
HeuristicLab Storage
jMusic Music Score
Teli Fax Image
Matrix Market File

The .hm filename extension is often given incorrectly!

According to the searches on our site, these misspellings were the most common in the past year:

nm (1), mh (1), hl (1), hj (1), gm (1), ym (1), tm (1), mm (1), jm (1), hk (1), hh (1), um (1)

Can't open a .hm file?

If you want to open a .hm file on your computer, you just need to have the appropriate program installed. If the .hm association isn't set correctly, you may receive the following error message:

Windows can't open this file:


To open this file, Windows needs to know what program you want to use to open it. Windows can go online to look it up automatically, or you can manually select from a list of programs that are installed on your computer.

To change file associations:

  • Right-click a file with the extension whose association you want to change, and then click Open With.
  • In the Open With dialog box, click the program whith which you want the file to open, or click Browse to locate the program that you want.
  • Select the Always use the selected program to open this kind of file check box.

Supported operating systems

Windows Server 2003/2008/2012/2016, Windows 7, Windows 8, Windows 10, Linux, FreeBSD, NetBSD, OpenBSD, Mac OS X, iOS, Android