What are some of the signs of a dangerous online business scam?

If through e-mail OR social media accounts:

1. If it is in junk mail then the email service already did the job for you using industry standards for indentifying spammy, spyware-bearing, scam or phishing emails (with the intent of getting vital information from you)
2. Email address is fishy: the name does not correspond with address.
3. If it is not labelled as junk but it contains a name that does not correspond with address, generic non-personalized messages, usually concerning fake romantic relation propositions, invitations to websites (if you place the mouse on the link, you can see the actual shady web address in the down-left corner of browser), or it contains a request for bank account information, implausible business offers or requests for (receipt of) money transfer.
4. If from a social account, the account is almost inactive, ghost-account with no picture or a celebrity picture or a fake one. It has little to no activity and no followers but a lot of following others. It does not have any account with its name, or other similar ghost social accounts with same name.

If a website:

1. The website has no trade register or chamber of commerce registration number, while still active in communication. Or the stated numbers cannot be found in register.
2. The website has a weird name and image, usually too long in name and too long in pages (mostly a one page website with a call-to-action in the bottom)
3. The website is poorly designed & built in a deviant way, with no standard sections like [about us] and [contact].
4. The website states no physical addresses or phone numbers and no other official registration information (trade register, VAT number etc) to confirm its strictly digital nature.
5. The website has no e-mail address but only an embedded web form with a clear lack of credibility. (many credible websites state no email addresses as anti-spam measure)
6. The website requests upfront payments or submission of payment processing information with few or no guarantees at all.
7. The payment process does not lead to a clear break-down of the amounts to be processed (including or excluding VAT and shipment costs) before confirmation.
8. The website directs to a non SSL-protected payment area (the right side of web-bar changes in blue colour (sufficiently secure) or green colour (secure for payments & internet banking) and the address is preceded by https:// instead of the normal http://)
9. The e-commerce site has no customer service section or contact-data at all.
10. The website has little to no online presence in business directories and credible sites, or no other presence in search engine at all. There are no (realistic) reviews to be found about the e-commerce website.

As in the offline world, the Internet has a criminal element. These cybercriminals are using Internet tools to commit the same crimes they have always committed, from robbing you to misusing your good name and financial information. Learn to spot the types of scams that occur online and you will go a long way towards steering clear of Internet crime.

The warning signs of fraud

BEFORE you click on a link that comes in a forwarded e-mail message or forward a message to others, ask yourself:

Is the information legitimate? Sites such as TruthorFiction, Snopes.com, or Urban Legends can help you learn if the e-mail is a scam.

Does a message ask you to click links in e-mail or instant messages?  If you're unsure whether a message is genuine, call the company using the number from a past statement or the phone book. To visit the Web site, type the address if you know it or use your own bookmark rather than clicking a link. If the Web site is new to you, search for the company using your browser and use that link to visit their site.

Does the e-mail have a photo or video to download? If so, exercise caution. If you know the person who sent the photo, it is probably fine to download, but if the photo has been forwarded several times and you do not know the person who sent it originally, be careful. It may deliver a virus or other type of malware to your computer.

Think before you click, and save yourself and others from scams, fraud, hoaxes, and malware.

Any kind of attractions for easy money or free gift or any thing coming free!

the person asking bank details and personal info.

One Basic for all Scams. "TOO Good To be true".