There is no 3645-C form or letter that I can find on the IRS website. Not even a reference to it. Is this a state thing maybe? However, there is an IRS Form 3645 which is used to figure the penalty for a business with employees that did not do proper reporting of the 940 on employee wages and the employer contributions on the social security and Medicare tax. My screen shows "unknown" for whatever version and flavor of the TurboTax program you're using. So without knowing what type of return the letter is for, I'm making wild guesses here based on no facts. Generally, the 3645 letter relates to a 1065 Partnership Return, or an 1120-S or 1120 Corporate return.
IRS Letter 2645C is a notice that the IRS is delaying your case. Is that what you got?
Yes, I made a mistake in the number, it is a 2645c. Thanks for the clarification!
they needed more information and they will contact me in 60 days.
I must say that I am on disability and I did claim my daughter as a dependent since she spends more than 6 months out of the year with me.
From what I see on the sample letter on the IRS website, it would appear there is no "problem" per-se - at least so far. I get the impression is that the IRS is just informing you there is a delay in processing your return. Therefore they provided you a curtsey notice of said delay, so you don't get to concerned about not receiving your refund in a timely manner.