H1W file format description

Many people share .h1w files without attaching instructions on how to use it. Yet it isn’t evident for everyone which program a .h1w file can be edited, converted or printed with. On this page, we try to provide assistance for handling .h1w files.

1 filename extension(s) found in our database.

.h1w - Microsoft Help Merged Keyword Index

The H1W data files are related to Microsoft Windows Help. The H1W file is a Microsoft Help Merged Keyword Index. Microsoft Help is a system assistance program included with Microsoft Windows.

Microsoft Windows Help
Data files
- / -
Microsoft Help Merged Keyword Index related extensions:
Anritsu IQ Producer Waveform Data
GameExchange2 Material Data
General Data File
BV QSL Management Data
Reason NN19 Sampler Instrument Patch
Advance Design Results File

Naturally, other applications may also use the .h1w file extension. Even harmful programs can create .h1w files. Be especially cautious with .h1w files coming from an unknown source!

Can't open a .h1w file?

When you double-click a file to open it, Windows examines the filename extension. If Windows recognizes the filename extension, it opens the file in the program that is associated with that filename extension. When Windows does not recognize a filename extension, you receive the following 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 one from a list of programs that are installed on your computer.

To avoid this error, you need to set the file association correctly.

The .h1w file extension is often given incorrectly!

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

g1w, h1, h1d, h1q, h1s, hlw, hw

Is it possible that the filename extension is misspelled?

Similar file extensions in our database:

Microsoft Help Compiled Help Data
Hioki Logger Communicator Waveform Data
Casio fx-9860G SDK Project
Marvelous Designer Hardware ID Data
Bruker Aspect NMR Data
Microsoft Help Validator File

Operating systems

DataTypes.net currently supports the following operating systems:

Windows XP/Vista, Windows 7/8/10, Windows 11, CentOS, Debian GNU/Linux, Ubuntu Linux, FreeBSD, macOS, Mac OS X, iOS, Android

If you find the information on this page useful, please feel free to link to this page.


If you have useful information about the .h1w file format, then write to us!

DataTypes.net >> H1W file