The Bank of Scotland was criticised by millennium campaigners last week after refusing to name a supplier it accused of providing non-Year 2000 compliant software.
Speaking at the release of the bank's annual results, governor Sir Bruce Pattullo revealed the findings of Project Task Force - set up in 1996 to make the bank's IT systems Year 2000 compliant.
"The project uncovered significant areas of non-compliance in certain software packages which had previously and erroneously been certified Year 2000 compliant by the supplier," he said.
But despite taking remedial action against the software provider, the bank refused to give details of the company.
Robin Guernier, director of Taskforce 2000, the independent Y2K awareness group, criticised the bank's silence.
"The Bank of Scotland is promoting misinformation if they are attacking the supplier but not releasing any more information. What have they got to lose? This is something people need to know about as quickly as possible," he said.
Action 2000, the government body responsible for awarding Year 2000 compliance logos, declined to be drawn into the controversy. It would only say that every supplier of Year 2000 products should register with the Computing Services and Software Association (CSSA) - even though this was no guarantee of official accreditation.
Tony Lewis, deputy director of the CSSA, said: "We have to know both sides of the story - software packages don't work in isolation."
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