Computer services to 80 UK hospital trusts in the North West and West Midlands, were downed following a power cut at the end of July.
IT experts from CSC and sub-contractor, Hitachi, worked around the clock, to restore access to data centres affected by the power supply interruption.
In a statement released by NHS Connecting for Health (CfH), the agency responsible for health service IT, said services provided by CSC Alliance for the NHS in the North West and West Midlands had suffered serious interruption' since 10.00BST on 30 July.
CfH went on to say that the incident was the result of storage area network equipment failure, and had affected several organisations using the CSC Maidstone data centre. It added that data held in the central data centre for the region could not be accessed due technical issues' and that the nature of the incident meant that service could not immediately be provided by the back-up systems, also provided by CSC Alliance.'
No data was reported lost during the interruption.