A £140?million IT shake-up at Birmingham City Council was introduced with inadequate staff training and poor input by managers, an inquiry has concluded.

Hundreds of employees who should have been shown how to work under the new arrangements were not properly trained, while others who would not come into contact with the Voyager computer system were given training - a fiasco that quickly led to a backlog of more than 30,000 unpaid invoices.

By the beginning of this year, three months after the new system was installed by Capita-led Service Birmingham, small businesses were forced to use bailiffs in an attempt to get hold of the money they were owed for supplying goods to the council.

Senior local authority finance officers had to write cheques by hand while Voyager “teething problems” were investigated.

Voyager is now working well with about 95 per cent of bills being paid on time, according to the council.

The new computer programme, part of the Customer Services Transformation project, is designed to modernise the way the council settles its bills and buys more than £1 billion of goods and services. It is supposed to deliver savings of £860?million over 10 years.

A “lessons to be learnt” report by Glyn Evans, head of business transformation, said that staff who were expected to use the new system were not properly briefed and supported. The report adds: “Many people in the council didn’t think Customer Services Transformation was going to happen or think the changes applied to them.

“The engagement strategy used relied heavily on managers of all levels to cascade information and it is now recognised that this didn’t work as well as expected. Most engagement took place well into the project and by this stage there was an element of frustration on all sides which led to the council being less willing to listen.”

Communication with staff was “jargon-ridden” and there was a failure to properly identify the 600 people who would have to operate Voyager.