First of all, look out for the sender's email address. Most of the spammers out there do not have a proper email address. Verify the email from that on the official page of the organization name from where they are claiming that they have sent the email. Fake offer letters usually claim for money and the process for getting a job might be looking very simple in the fake offer. For example, I really offer involves an interview, selection, and other processes. Fake offers will straightway give you the job and ask you to transfer money to some account. I would also suggest to call the office and get confirmation from them that you have received from them only. If you receive any email of this sort, always do a through check of the sender.