The letter and check from Reader's Digest Lotto look real. It is a scam. Our letter showed the writer to be Derek Williams as the Chief Financial Officer.
The check shows Foley Hoag, which is a legitimate law firm and it has their correct address in Boston. I verified with the law firm of Foley Hoag that this letter and check is a hoax.
The letter asks you to call a number to activate your claim for a significant prize. The number is not the law firm--but another number with a recording. I am hoping there is not a significant telephone charge for calling this number, but I suspect there is a charge and that is how the scam works. Hope this helps others who receive the letter.