"It's being used as a test box to compare things until we upgrade as the client doesn't run on XP," O'Ryan said. "We probably won't run the Windows 98 box past the deadline as the upgrade is due [for completion] in two weeks."

At its peak, IP Australia had around 1000 Windows 98 desktops which were quickly upgraded to Windows XP over the space of "a few weekends".

"We never really contacted Microsoft, or used the support anyway," O'Ryan said, adding she doesn't think there are many Windows 98 installations left within the wider enterprise.

O'Ryan said IP Australia is "having a look" at Windows Vista, but could not reveal any upgrade plans.

Echoing O'Ryan's stance, an IT project manager at a utility company, who requested anonymity, said while there are only two Windows 98 machines left running logging software, the decision to end support is "not a big deal for us".