qmail options or services file
File type: Settings, options, themes or skins file
A .qm4 file is a qmail options or services file. It contains settings used to configure qmail-related services.
It is a text-based configuration file associated with qmail on Linux and Unix systems.
File type category:
Settings, options, themes or skins file
Date updated: September 27, 2026
qmail is a mail transfer agent for Unix-like systems. A .qm4 file stores options or service settings for a qmail installation rather than email messages or user data.
The file forms part of the qmail configuration and is interpreted according to the service or setup that uses it. Its contents and location can therefore depend on how qmail was installed and administered.
A .qm4 file can usually be opened as plain text with a Linux or Unix text editor. The file should be edited only by an administrator familiar with the qmail installation and its service configuration.
Use a text editor that does not add formatting or change line endings. Make a backup before editing, and preserve the file's expected name, location, and syntax so that qmail services can continue to read it.
There is no standard conversion utility for the .qm4 file format. Its contents are configuration settings, not data intended for export to another file format.
When moving qmail to another installation or mail system, the settings usually need to be reviewed and adapted manually. Copying the file without checking service paths and supported options may not work.
Software apps that manage or store settings in qm4 files:
Linux/Unix
Language
