A spokeswoman for Social Services Minister Helena Jaczek says the bug with the new software system was fixed within "24 hours" after being caught Monday during its maiden payout.
Amber Anderson says the software allotted $20 million in money transfers and cheques to 17,000 clients with the Ontario Disability Support Program and Ontario Works welfare program.
She says 11,000 of the payments to individuals or families were stopped before they went out.
Anderson says around 6,000 of the wrongful direct transfers and cheques did make it out the door but were either pulled back or cancelled — though 253 clients did receive a total of around $300,000 yet to be retrieved.
The Ministry of Community and Social Services says in a statement case workers are getting in contact with those clients to try and get the money back.
It says officials are continuing to monitor the new Social Assistance Management System, and that additional staff have been sent to the front-line offices to help familiarize them with the software, which is tasked with handling 500,000 cases.
"Support staff will continue to help local offices make this transition successful," the statement said. "The ministry continues to address system issues and make necessary adjustments."
Tory social services critic Bill Walker said Jaczek and ministry staff had told MPPs in committee earlier this month the transition to the new software would be "seamless" but that the result is anything but.
"It's one thing to give them some slack and say, this is expected, there's always going to be some minor ripples. But they assured us," he said in an interview Saturday.
"And if they weren't 100 per cent confident that the most needy in our society weren't going to have glitches then they should have not implemented it" without first ensuring it worked, he added, while questioning both the behind-the-scenes cost of the error and the number of people it affected.
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