1) Does this happen on one site or multiple sites?

2) In one of your replies, you show a tight loop without any chance for the site to recover. Think about adding a sleep interval before resubmitting the request.

3) Be aware that most sites will throttle you if you send too many requests (search the web for Denial of Service).

4) You said you "saw other post with same problem". Do not expect us to search for the post, reference it within your message.

5) The problem could well be with your ISP, rather than perl ;-) .

6) Please read the replies to your post prior to saying that we did not solve your problem.