I see this message "The last posting from your IP was less than 360 seconds ago. Please try again later."
but my last message was several days ago, and overtaking your ideas:
1 - I have 3 days ago installed windows, where only Chrome\FF with all plugins disabled (Flash etc.)
2 - My current IP has not changed in a few days, and it dedicated IP not shared
so can this be forum bug?.. if no, I am very interested to see this message what was posted from my IP 360 sec ago
It is quite confusing , as it includes logins , PMs and posts.
Don't worry , just continue posting for a couple of weeks and it will stop happening as your activity reduces.
Once you cross 15 activity , your post cooldown shall become (90 - activity) , 75 seconds.
Once you cross 60 activity , your post cooldown shall become around 30 seconds.
Finally , once you cross 100 activity, your cooldown will be 12 seconds , dropping by 1 second for every additional activity , down to 4 seconds.
At around 60 activity itself , you will have a short enough interval such that it won't really matter. Continue posting and contributing , your post interval shall reduce rapidly.