I’ve discussed the frequent scams with crooks calling on the telephone pretending to be from the IRS.
Snopes has some tips on avoiding email based scams of the same kind.
Tax season in 2016 triggered a number of novel riffs on common Internal Revenue Service-based scams.
The moral of the story is to always check with your own professional tax advisor before making any response to any type of communication from the IRS, including legitimate ones via snail mail.
Tax Guru - Ker$tetter Letter 