The new, colored $20 bills designed to make counterfeiting more difficult are also making it tougher to use automated payment machines.
It seems many of the machines, like those found in self-service checkout counters at grocery stores, reject the new bills.
The problem is especially vexing for officials at the Treasury Department's Bureau of Engraving and Printing, which worked to overcome the vending machine problems that occurred when the bill was redesigned in 1998.
The first calls about the automated payment machines started coming into the Treasury office two days ago. The machines are a relatively recent arrival.
Some companies have put up signs advising customers not to use the new bills. Others plan to upgrade soon.