I'm using Hostgator and as I know my current IP is not blacklisted unlike my previous one which was.

--------------- Added [DATE]1420303711[/DATE] at [TIME]1420303711[/TIME] ---------------

Edited........ Idiot me.. Has nothing to do with hosting but with my ISP

Ah ok I was not sure. Seemed pretty strange.

what's this?? :confused:

Well it would be something like this, Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.116 Safari/537.36

Go to your online page on your site and choose to show useragent string.

What if I say that I understood nothing? Should be that I've IQ 1? Which online page and where to choose to show that string? Do you mean in my vB admincp?

Nope, on your vB site, go to online.php

Then at the bottom of that page you gave a select box that is titled,
User Agent: set that to yes, and then click on the Display button.

Once the page refreshes, get the useragent string for yourself, and paste it here.

After 5 years using vB4 it's the first time that I'm seeing this page.
Mozilla/5.0 (Windows NT 6.3; WOW64; rv:34.0) Gecko/20100101 Firefox/34.0

But as I said I got the same message when tried to register with IE, Chrome and even Opera. I think that in those case the useragent should be different.

Ok, what hosting provider are you using for your internet?

I've removed my IP. The rest is: dsl.dyn.forthnet.gr
Forthnet is my ISP

Ok, you should be able to register now. :)