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Why is my IP blocked at a website I visit regularly after I changed ISPs?

Question:

I just installed a new Express Card with Verizon Broadband wireless last
night. Had tons of fun accessing the web from places I usually cannot, (we are
in trucking) until I got to my favorite forum. It’s a public place I have been
to thousands of times, but instead of happily browsing all the daily news
events and checking to see if the world blew up yet, I found myself blocked by
a big white screen that said YOUR IP ADDRESS HAS BEEN BANNED.

What can I do? I can’t go to the forum owners to tell them it’s just lil ‘ol
me. Besides, I have picked them up on all other wireless connections at various
hotspots I run into, so what’s up? Do they not like my new Verizon service?

I’m sure they like the Verizon service just fine. What’s more likely is that
someone else who also used the Verizon service broke a forum rule or something
and that got him banned.

Unfortunately this demonstrates one of the problems with IP-based banning or
identification. It frequently doesn’t work. There’s a good chance that you’re
blocked instead and the original user can get right back in.

There are roughly three things you can do.

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As you know by now every computer connected to the internet is assigned an
IP address. Those addresses are assigned by your ISP, statically (a permanent
assignment) or dynamically when you connect (a temporary assignment).

In the case of Verizon’s wireless service, your computer is assigned a
dynamic IP when you initially connect. The computer retains that IP address as
long as it’s connected to the network (I’ll have a small caveat about that in a
moment). When you disconnect that IP is returned to Verizon’s available pool of
IP addresses where it might be assigned to the next person to come along and
connect.

In other words the IP your machine is assigned today may have been assigned
to someone else before you.

So here’s what’s most likely happened:

  • Person A comes along and connects to the internet via Verizon’s broadband.
    They’re assigned an IP address.

  • They visit the forum you’re also wanting to visit and they raise heck. The
    administrator of that forum says “enough of this”, notes what IP address
    they’re posting from, and blocks it.

  • Person A disconnects.

  • Some time later you come along. It could be minutes, hours, or days later,
    but you’re randomly assigned the same IP address that Person A was using when
    he (or she) was causing problems.

  • That IP is still blocked at your forum. You pay the price for someone else’s
    behavior.

“In other words the IP your machine is assigned today
may have been assigned to someone else before you.”

The ultimate irony is that Person A can probably reconnect, randomly get
assigned a different IP address, and continue posting.

However, the forum moderator could deal with that irony by blocking
all IP addresses which originate from Verizon’s broadband. ISPs are
themselves assigned blocks of IP addresses, and it’s relatively easy to block
an entire range.

Unfortunately there’s no real way for you to know what’s happening.

Here are the options as I see it:

  1. Disconnect and reconnect, hoping to get a new IP address. (Run “ipconfig” in
    a Windows Command Prompt to see the IP address that’s been assigned to your
    Verizon connection.) Caveat: you may want to make sure to power down the
    Verizon Express card and then turn it back on. It’s possible that even though
    “disconnected” it may retain its IP address while powered on. If you get a new
    IP address, then you may be able to visit the forum. If you can’t, chances are the
    entire range is blocked and you’ll have to take the next step.

  2. I know you said you can’t just go to the forum owners, but in fact that’s
    what you’ll have to do. This isn’t something that you’ll be able to side-step
    without their help, especially if they’ve blocked an entire range of IP
    addresses.

  3. Use a different ISP. As you say, you’ve been able to access this forum at
    various Wifi hotspots, and perhaps that’s what you’ll need to keep doing if you
    can’t get the IP block removed. Use your Verizon connection on the road and
    wherever else it makes sense, but get your forum “fix” by firing up the Wifi at
    local hotspots along the way.

OK, there’s a fourth option: use a proxy. Something like Anonymizer will
route your traffic through their servers, making it look like it’s
coming from their IP address instead of yours. There are several such services of varying complexity, speed, and cost. I’ve not yet used one myself.

For the record I also recently got a Verizon Express card and have been
quite happy with it. Or rather, my wife has, as she recently spent an entire
1.5 hours on the road running her business remotely while I was driving us down
the freeway.

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9 comments on “Why is my IP blocked at a website I visit regularly after I changed ISPs?”

  1. Is this why i’m having all of these problems? I thought my computer was a piece of crap I just bought in November and I was ready to toss it out the door!!!

    Reply
  2. hello i wonder if you can help i have been blocked and banned from a site through my stupidity but want 2 get back into the site i have asked my internet provider and they said that my ip is okay it could be the site that i am trying 2 get back on has blocked my ip themselves at there end can you help me please as i am desperate in getting back on to that site many thanks christine

    Reply
  3. I have limited access to the internet in work, however my seniors have full access. How can I change my IP address to enable me full access?
    My IP address ends in 2 figures i.e. 27, however my seniors(with full access) end in 3 figures i.e. 112. How can I find out a 3 figure IP address which isn’t in use,without having to guess, as I would be afraid of using some one elses?

    The number of digits has nothing to do with it. Unfortunately there’s not enough for me to go on to make a guess as to what the problem actually might be.

    Leo
    14-Sep-2009

    Reply
  4. Can a home user block an ip from your network or computer?

    Firewalls do this but how can I do this??
    or what is the theroy behind block an ip address?

    Reply
  5. I am deployed with the US military. I am in a location without much military support. We are in a rented facility using a rented internet service. I’ve been able to get on to Navy Federal Credit Union every day until yesterday. Now I get a message that says Internet Explorer Cannot Display the Website. I get the same error when I try to view my son’s grades on powerschool.com. I don’t even get to the website so I cannot even contact them to tell them about the problem. Any suggestions?

    Reply
  6. Great article Leo,

    I was just for this, I was wondering why these sites block someone with the ip? Isn’t there any other way ? Cookies may work sometime for a while!

    I think blocking IP is a old trick when IP address used to be static.

    Reply

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