As Computer Weekly went to press, EDS was on course to deliver the new software on its due date of 6 November. The CSA's IT systems were slammed last month by a Commons select committee. The agency's chief executive Doug Smith also resigned.
Preparations for the CSA update were taking place as investigators from EDS and Microsoft struggled to pinpoint the cause of a crash that hit 80% of the desktops in the Department of Work and Pension following a software upgrade on Sunday 21 November.
Two weeks after the incident, the DWP told Computer Weekly, "The cause of the problem still has to be determined."
A routine software upgrade affected the functioning of PCs and prevented some users from accessing their business systems, the department said.
Internal DWP documents seen by Computer Weekly show that thousands of civil servants could not access key systems. Two days after the crash a memo read, "EDS and Microsoft have been unable to establish the root cause of the continuing issues that are being experienced throughout the DWP estate."