Support for related products is scheduled to stop one week later, but continuing support will be available under a service contract.
OS/2 went head-to-head with Windows in the early market for desktop operating systems. Although it was considered technically superior, the software lost out to Microsoft owing to a limited selection of applications.
IBM's operating system had a particularly strong following in the financial sector, powering many ATMs.
The last version of the software was published in 1996, although Big Blue has continued to maintain the software and has been releasing patches.
IBM has advised the few remaining customers of OS/2 to switch to Linux.
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