Consult your sources. If you find a job offer that interests you or if you get a job offer out of the blue, search for the company on the Internet and contact them directly to confirm that both the recruiter and the job offer are legitimate. Search for the company name and scam, then see what appears. There are several steps to reporting a job scam, but you can prevent a lot of people from being scammed.
In a nutshell, no legitimate company will ask you for a job interview through a courier service. Since most of these offers are made through emails, performing a fraudulent verification would be a decent way to address the problem. Shortly after the interview, they grant you the job opportunity and provide you with a series of work documents to receive your personal and banking information. If you're looking for work, you probably have a good idea of what the average salary is for your job and your level of experience.
Most open positions receive a lot of applications, so it's rare for a recruiter to have to search for qualified candidates on job sites. The increase in cases of fraudulent job offers makes it a touching time to learn how to recognize and avoid being a victim of fallacious job offers. If you receive a job offer letter with capitalization issues, missing commas (or too many) and generally bad English, it may indicate that the offer isn't real. If you find a job offer that shows that position for two or three times the typical salary, be careful.
If you can't figure out what you would do in a particular job based on the description, assume that you don't want to know. Online employment websites and social media sites are aware of these scams and are continuously identifying and removing fraudulent job profiles and offers. The scammer contacts you (they're very friendly, polite and professional) with a job offer and starts an online interview via email, video chat, or text message. A job offer should be easy to read and understand, and that doesn't mean there can't be one or two typographical errors.
Post your resume on an employment website (LinkedIn, Monster, ZipRecruiter, Facebook, Indeed, Craigslist, Kijiji, or CareerBuilder) or a scammer creates a job offer on one of these websites.