I am not asking the question via PM. Just informing them about my thread by including the link only !

What is spam?

Spam is flooding the Internet with many copies of the same message, in an attempt to force the message on people who would not otherwise choose to receive it. Most spam is commercial advertising, often for dubious products, get-rich-quick schemes, or quasi-legal services. Spam costs the sender very little to send -- most of the costs are paid for by the recipient or the carriers rather than by the sender.
I am not forcing the people to help me. Just letting them know.

For a previous thread of mine, I had send PM's to most of my contacts. Some of them replied via posting solutions to thread. And some via PM (because, I managed to RESOLVE the topic soon. Some of them had logged in after the thread was solved. So, they send the reason via PM - as a reply to mine!).
But one of them replied that he/she won't accept requests like this. For that person, I send my apologize via PM and thanked for replying. And in the future, I won't send PM to that person....