Microsoft is urging an estimated 70 million users of Windows 98 to upgrade as it ends support for the software.
From 11 July, Microsoft will no longer help users over the phone with any problems they have with the ageing operating system.
The firm will also stop providing security updates for Windows 98 from the same date.
Support for the software was originally due to end in 2003, but was extended following customer protests.
I have windows 95 on my real old comp