Many forums have rules about posting links so you see a lot of weird posts like this one...you most post 3 times before you can include links for example. Other forums have rules about introducing yourself so you see a lot of vague "hello everyone" posts. The next bit of suspicion was spelling/grammar.

"My name is Hassan and I have just joined this community, this is my first post here just to say a hello to all the member of this forum. "

Note the perfect spelling...caps on the I then the "i am from asia or russia" grammar...

"just to say a hello" and "all the member of this forum".

English speakers who can spell and use punctuation also know how to phrase sentences properly. No one says "just to say a hello" and members should be plural.

Most people who join forums make their first post about something like "where can i download URC software?". They don't drop by to say hello to everyone.