Microsoft WinHelp compressed data
File type: Archive and compressed file
A .h_ file contains compressed data used by the Microsoft WinHelp system.
It is a compressed Windows Help file that generally must be expanded before it can be viewed.
File type category:
Archive and compressed file
Date updated: October 22, 2026
The .h_ file extension is associated with Microsoft Windows Help, Microsoft's help system for the Windows operating system. It is used to create and view Windows Help files that provide documentation and reference information.
An .h_ file stores compressed WinHelp data. After decompression, the resulting Help file can be opened by the Windows Help viewer.
Microsoft Windows Help is a legacy Windows technology and is not included by default in many current Windows versions.
An .h_ file is compressed and generally cannot be viewed directly. On Windows, use the Microsoft EXPAND utility or another compatible decompression method to restore the original Help file, usually with an .HLP extension.
Open the expanded file with Microsoft Windows Help or WinHlp32.exe on a Windows system that provides the legacy Help viewer.
There is no normal conversion from the .h_ format to another document format. Expand the file first to recover the original Windows Help file. Conversion to other formats is not possible.
Software apps that create h_ files:
Microsoft Windows
Software applications that handle other tasks involving h_ files:
Microsoft Windows
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