An IT failure that occurred almost a month ago within parent company Royal Bank of Scotland’s (RBS) batch processing software, will cause Ulster Bank customers another week of disruption to some services.

A spokesperson has confirmed to Computerworld UK that not all of the backlog will be cleared until next Monday, although most balances are now correct.

An upgrade made to batch processing software CA 7 from CA Technologies is believed to be at the heart of the failure.

“The weekend has brought steady progress in the processing of automated payments and as a result, the majority of morning account balances for customers are now showing as they should on Monday 9 July,” said an RBS spokesperson.

“However, some items - such as cheques and manual lodgements have yet to be processed and therefore will not be reflected in account balances as yet. We expect that this week will be the last week of significant disruption for customers and that services should begin to return to normal from Monday 16 July.”

The problem has been compounded by conflicting explanations of the origin of the problem.

Last week, RBS told MPs, who called for an explanation to the problems, that its Edinburgh-based IT staff were responsible for the systems failure that affected millions of customers.

This contradicts earlier media reports that claimed a junior IT worker based in India had made the error. 

In his letter to Andrew Tyrie, chairman of the committee, Stephen Hester wrote: “The initial reviews we have carried out indicate that the problem was created when maintenance on systems, which are managed and operated by our team in Edinburgh, caused an error in our batch scheduler.

“This error caused the automated batch processing to fail on the night of Tuesday 19 June. The knock-on effects were substantial and required significant manual interventions from our team, compounded because the team could not access the record of transactions that had been processed up to the point of failure.

“The need to first establish at what point processing had stopped delayed subsequent batches and created a substantial backlog.”

For a preliminary analysis of the issues surrounding the RBS IT failure, click here.