Hi,

Having only 160 friends and even I know that person personnaly I am not able to send the request error message from Facebook is as "Do you know this user personally? To prevent misuse of Facebook, this request can't be sent. To learn more, please visit the Help Center. If you believe you're seeing this message in error, you can report the problem."

Please help in sloving the issue

Did you visit the Help Center, and did you report the problem? Obviously you think you're receiving the message in error, so report the problem like it says.

Sometimes, clearing the cache and cookies will allow you to avoid this error, but not always.

Check the solution they found at the bottom of this page:
Won't let me add a friend. | Facebook (http://www.facebook.com/topic.php?uid=2309869772&topic=10069&start=30&hash=3f9e78a00220642f5accdd4b9a906e08)

Do you know this user personally? To prevent misuse of Facebook, this request can't be sent. To learn more, please visit the Help Center. If you believe you're seeing this message in error, you can report the problem.

I'm delelet Facebook request

Having only 160 friends and even I know that person personnaly I am not able to send the request error message from Facebook is as "Do you know this user personally? To prevent misuse of Facebook, this request can't be sent. To learn more, please visit the Help Center. If you believe you're seeing this message in error, you ca

Do you know this user personally? To prevent misuse of Facebook, this request can't be sent. To learn more, please visit the Help Center. If you believe you're seeing this message in error, you can report the problem