About 445 of Wells Fargo Bank's 1,200 automated teller machines in California shut down temporarily on Wednesday because of a computer failure, the bank said.
The rare shutdown, which started Wednesday morning and lasted until late afternoon, affected ATMs mostly in the state's Central Valley, but some in Southern California were also hit, Wells Fargo spokeswoman Kim Kellogg said. No customer records or transactions were lost or ruined, but many customers were unable to use the automated tellers, she said.
"For the most part, people just went into branches and did it the old way," Kellogg said.
She blamed the shutdown on a failure of the communications link from a central processing unit to the ATMs, adding that the bank has not had a similar foul-up in at least seven or eight years, and certainly nothing of this magnitude.
"We don't remember when anything like this last happened," she said.
G. Henry Mundt, senior vice president of marketing at Cirrus System, a Chicago firm that operates the nation's largest ATM network, said computer-related shutdowns are rare because most ATMs are run by sophisticated computer systems with backups. "If there is a malfunction, the backups kick into place," he said.
Wells Fargo's Kellogg said the bank has backups, but because this problem involved wiring going out from a computer, the backups couldn't help.
While mass shutdowns of ATMs for prolonged periods are rare, machines are often turned off for a few minutes a day for standard servicing to replace money and receipts, Mundt said. ATMs operate on average more than 99% of the time, he said.