I seem to get a few Linked-In friend requests (technically, I believe they are “add to your networks”) a week.  I click on most of them and use a few quick clues as to whether the persons profile is a legitimate one:

1. If they appear to be “real”, I will usually accept.  “Non-real” is some combination of experience does not match age or some other gut reaction to whatever their profile shows.
2. If something does not match the profile, I may sit on it a couple of days and check back.  If the particular potential “friend” has acquired enough confidence from others, I may give another quick review.  At this point, I may accept, delete the requests, or camp on it a couple of more days.
3. If I choose to camp on it, it is certainly not a good sign if the profile picture changes on the last visit.  I am not talking a simple profile change.  I am referring to a picture of someone from a different race and likely from a different country.  When my revisit to this profile yielded a picture of someone who obviously was not the same as the person who invited me to their network, I delete any memory of the request every taking place. (See images above.)
4. Another request came from an old acquaintance. (Technically, this took place on Facebook.)  I will admit to calling him pushy and not nice or someone I would actively seek out as a friend.  Since he was a friend of a friend….well, you know how the Facebook thing works sometimes.  He “liked” a few things on my Facebook page before asking for my email address. (My profile did not show an email address.)  Having a strong desire to have him leave me alone, I acquiesced.  (I knew he couldn’t hurt me too much via email.)  His purpose for my email was a surprise.  He is trying to build up his “Yelp!” rating.  He wanted me to complete a rating for him singing his praises.  Not having seen him in 20+ years (also see earlier comments), I decided it was better to give NO rating than the one my very sincere fingers would have crafted.  Sorry demanding Facebook friend!
5. Sometimes, I get a little curious.  The other day, I received a request from someone who was from an African nation.  Their were a few flags, but she had enough “links” to look legitmate, so I decided to go with it.  Within a few moments of accepting the invitation, I received an Linked-In email requesting the best email to send an investment opportunity.  Still being gripped by curiosity, I continued down the road.  At this point, many of you have some idea what the road looked like.  It was paved with a dying client who had no children….

Her first email:

Thanks for getting connected with me as I will like to solicit your kind help and co-operation in a reliable business investment project that will benefit both of us in mutual partnership.
Please acknowledge receipt of the below message and your willingness to assist so that we can agree in terms and in principles. Myself and the board of directors.
Find my email address below. Contact me for further clarifications
I look forward to meeting with you in the near future.
Yours faithfully,

The “opportunity”….

How are you doing today? Hope the family is in good health. Thanks for
your response and interest. Please permit me to use this medium to explain
further to you my purpose of contacting you in this Manner.

We have a client who has been sick for the past 4yrs now and the wish of
my client is to reach out to the less privileged ones, who can’t make a
start of living for themselves. Three years ago she was diagnose with
cancer of the breast reported by the doctors in charge of her treatment
and medications, it was being described as a very deadly cancer which she
has to live for a certain period of years. And ever since my client has
been struggling with this very sickness.

Last year she called me and the lawyer and her cook, and made it known to
us what her condition is, that very day she made up her mind made a
statement on how her wealth would be shared after she is gone, but firstly
a good business successor has to take over from where she stop and a good
transformation with what she left behind, by working according to her
dream plans and wish. I request your kind assistance.

My client was the director of foreign affairs, Gold and diamond business
merchant, she was married to her husband Mr.Bionds and they both lived for
28yrs together without a child, so adopted a Dog and named it pew. The
husband pass away 9years ago, then left her with the dog and their cook.
She has a fixed deposit of some merchandise such as Gold Diamond with some
reasonable about of cash a long side with the security firm.

Which details would be given to you in your readiness to work hand in hand
with us to achieve her goal. Part of the cash is been willed to the dog
and the cook, while the other side of the items and cash would be used to
actualize her dreams in other to keep her name alive. I see you capable of
handling this business project with you position, which will beneficial to
us all as along we work together to see her words come to reality.

The item would be handed over to your company name the charity
organization will be handled by you as well, my duty is to make sure the
lawyer is accurate in his documentation to avoid any miss conduct.

Let me know if you have any question to the above message.

Thanks for your time and been connected.