MADISON, Wis. (AP) -- A Wisconsin Department of Revenue spokeswoman says about 1,200 state taxpayers are affected by a couple of computer errors by the agency involving out-of-state taxes.

Jessica Iverson says the first problem occurred when the state's computer system was unable to read the electronic form filed by some taxpayers seeking credits for paying out-of-state taxes -- the Schedule OS.

Iverson says the problem was compounded when this same group was erroneously sent notices without any explanation that they owed additional state taxes that were due by the end of the month.

She says those taxpayers should have first received a notice explaining why the agency believed they owed more taxes and given instructions on how to contest the amount and a 60-day period in which to do it.

Iverson says those letters will be arriving to that group of taxpayers next week.