Yes, this can be rectified. You have not done anything illegal, but you do need to file this past due return.
You simply need to file the return for the year 2006 and send it in with any tax payment that might be due. Alabama does charge a late filing fee on all returns. The amount of the fee is 10% of the total tax due or $50, whichever is greater. The minimum amount of $50 will be assessed, even if no additional tax is due with your return. If you owe additional taxes, there may also be some interest charged assessed to the amount you owe.
So other than possibly owing the state some money, you will not be in any legal trouble over the late filing of this return.
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