.12M File

.12m is Lotus 1-2-3 SmartMaster File

Key Features: .12M File Extension

Features Description
File Extension .12m
Format N/A
Created by IBM
Category Spreadsheet

What's on this Page

  1. How to open:
  2. How to convert:

What is an .12M file?

The 12m file extension is mainly related to Lotus 1-2-3 SmartMaster program from IBM and used for one of its default file types.

Old program used in 80s and 90s.

This 12m file type entry was marked as obsolete and no longer supported file format.

This type of file is no longer actively used and is most likely obsolete. This is typically the case for system files in old operating systems, file types from long discontinued software, or previous versions of certain file types (like documents, projects etc.) that were replaced in higher versions of their original programs.

Files with 12m extension could be found as part of old Lotus 1-2-3 suite in a program called SmartMaster.

How to open:

This file type is not meant to be opened directly, there is no software that could open and work with it directly, or there is no information available in public sources about opening this file type. This is usually the case of some internal data files, caches, temporary files etc.

How to convert:

As far as we know, this .12m file type can't be converted to any other file format. This is usually the case of system, configuration, temporary, or data files containing data exclusive to only one software and used for its own purposes. Also some proprietary or closed file formats cannot be converted to more common file types in order to protect the intellectual property of the developer, which is for example the case of some DRM-protected multimedia files.
Lotus 1-2-3 SmartMaster File - File openers


  1. IBM Collaboration Solutions




How to solve problems with 12M files