“I somehow filed my information for Ohio State school district taxes for 2010 on the 2009 form. I have a confirmation number that it was filed on time and taxes paid, and I was actually due a refund. I received a notice that I did not file and taxes due along with penalties and interest. I can easily prove taxes were paid, but since I actually did file...just on the wrong year's form, should I be assessed interest and the penalty for not filing or because it was on the incorrect form (year) am I still liable for the interest and penalty or just penalty...or nothing if I can explain that it was an error with the form only.”-------->Assuming that you filed a 2009 Ohio State school district tax return they'll reject it as a duplicate or as they will see the duplication(eventually) and probably notify you which one to consider correct; you should probably file the 2009 on the correct form and get that at least in the system. However, 2009 return was accepted, you do need to prepare the correct return and file 2010 return ASAP. You need to make any correction to your return by fi ling an amended school district income tax return (Ohio form SD 100X) for the year , 2009,that you are correcting using the correct 2009 numbers. You owe Penalties and Interest on your 2010 return;as you fi le your 2010 return after the unextended due date and you paid and/or will pay any tax after the unextended due date, you owe interest unless the refund, if any, shown on line 14 is greater than any tax you paid after the unextended due date. Interest is due on late-paid tax even if the IRS has granted you a fi ling extension. The year 2010 interest rate is 4%.Pease contact the Ohio Department of Taxation for more info on your issue.