"We had to make some changes in our approach sometimes," said Mark Powell, director for Retail Board UK at HP.
"We found we needed more expertise from Halfords on-site to do the testing."
Carrying out such a major overhaul also affected the whole business because all major business projects - except for the development of the Car Parts Direct service - were frozen while the new SAP system was implemented between December 2013 and May this year.
It was important for the system to work straightaway without any issues as the company was unlikely to accept such a "broad change freeze" again, Barsby said, adding that the system was live by the set deadline, and that "everything worked".
Other achievements and the future
Moving to the managed cloud service has allowed Halfords to consolidate its data centres, going from nine to four. Virtualisation has also removed 4.5 tonnes of hardware and saved £40,000 a year in electricity bills, Barsby said.
She added: "This year is about rationalising apps."
Many retailers are investing in making their supply chain systems more efficient to enable click and collect, which is seen as a way to bridge the gap between online and bricks-and-mortar stores. However, Barsby admitted that Halfords does not yet have a seamless, single view of its customers across the different channels.
"CRM is a big part of our agenda," she said of the company's future plans.
Earlier this year, Halfords announced it had signed a contract with Fujitsu for three years of IT maintenance and support, taking over from IT services provider Barron McCann.
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