In addition to Mike-In-MD's correct answer, read this ... carefully!
http://www.fdic.gov/consumers/consumer/news/cnwin0607/scams.html
Extract:
"In these cases, the depositor most likely will be held responsible for the entire amount of the fraudulent check."
Instead of cashing the check, or sending it back, take it and the envelope in which it came to the post office. They will use it as evidence and pursue the scammer.
I received a check for 2975.00 on Mountain America Federal Credit Union.I received a message on my email for a job paying 500 a week.The gentleman's name is Benny Steiner.Nice name,guy calls and he's Indian.He emailed the next day and told me to send 2475.00 to a gentleman in Missouri.I googled everything.His name,the bank,the company he works for,the company where the check was mailed from,ALL FRAUDULENT.ONE BIG SCAM.BEWARE ALL THEY WANT IS YOUR MONEY.Told him the money would help pay off my daughter's funeral expenses.They don't care about you.STAY AWAY.
I received a check for $2,795.00 via USPS priority mail. This new fraud scam wants you to buy Green-dot Cards from CVS or Rite Aid stores for $500 each. I guess with the money on these cards it will nearly untraceable. DO NOT DO IT!!!!!!
I also recieved a cashiers check today from Mountain America Credit Union. I almost bought it since that credit union is here in Salt Lake City Utah and the check is from their branch in West Jordan Utah. But then it jumped out at me as it states its "Payable through the Bank of New York Mellon, Everett WA. Well why does it have a Utah credit union name and and payable from another back east?
Just got 2 in the mail today for 1,998.86 and 1,997.11 both comes with a letter to where to send it. I also was on Craigslist about the assistant job. Mines dont have a number but address and western union it. I have done this before and cash it but i told the lady at the bank to check it and wait until it clears then ill get the money out she ain't do her part so I wasnt responsible at that time but I wouldn't do this any more.