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I logged in to a forum on two separate instances with a different ID each time. Someone actually was able to find out that this was me logging in with different IDs. My question is, how can any forum participant know my IP? I know that the forum logs the IPs, but am surprised that a member was able to identify my IP. My IP is not visible on the forum.

There's a lot that's not specified here, so I'll have to make a few assumptions. My first assumption, of course, is that you had a good intentions using different IDs on the same forum, and that you you're not trying to deceive someone. (See my rant on ethics if you wonder why I care.)

Depending on things, I can hypothesize several different ways to tell it's you, and not all involve IP addresses.

You didn't indicate which forum, or more importantly, which forum software is in use. It's quite possible that the forum software may not display your IP address, but could still embed it in the HTML. A "view, Source" of the a forum page will tell you that quick enough.

The forum software might make the IP address information to forum administrators. So you, as a "normal" user might not see it, but an administrator of the forum quite well could.

It might not be your IP that they're tracking, either.

"... it could be something as simple as your writing style."

Most forum software uses cookies to track user sessions - typically so that you only have to login once, and not each time you view a new page. If you visited the forum from the same machine in both cases, it's possible that the cookie, or information it contains, is trackable. Again, either by a forum administrator, or hidden in the HTML of a forum post.

The forum might include information that could be tracked to the same machine or IP in your user profile.

Finally ... and many people don't get this at all ... it could be something as simple as your writing style. We each have our own style - including common errors and grammatical nuances - that is fairly consistent when we write. A sharp observer could possibly be looking at posts you've made under both ID's and noticed that they're written in nearly identical style.

I've actually experienced this one at least one mailing list where a member who supposedly left clearly returned by writing using her husband's membership. Her style was quite obvious, and distinct from her husband's.

So as you can imagine, there are many possibilities.

The best solution, of course, is not to need to play these games in the first place. But I know that there are sometimes appropriate and valid reasons. I've even done it myself.

Article C2582 - March 5, 2006 « »

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Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

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April 25, 2006 1:54 AM

How can i use two different ID same time at my PC. i.e. I want to use two different Yahoo ID same time and want to talk with two different persons.


December 31, 2009 4:56 PM

This was very helpful. However, to expound on the original question - If someone is posting on vBulletin (let's say), there's no way a non-administrator has access to your IP address, correct? If this is true, then how would a regular forum member with no admin privileges know you were using two accounts? This is not necessarily a question of ethics from the vBulletin user side than a question of ethics from the administrative side; as it is a possibility that the forum leadership could be alerting some membership to privacy details without your knowledge. If a user is running multiple accounts, the administrators have the responsibility to handle that quietly on the side and notify other members of the action only if needed.

I'm no vBulletin expert, but it wouldn't surprise me if there were a way to get the IP address of posters. Even if not there are many ways to determine that two accounts are the same person: everything from writing style and consistant typos to images that all happen to refer to the same image server, to who knows what else. And of course if the admin can't be trusted all bets are off anyway.

May 18, 2010 4:30 PM


Tel:00228 9321649.



Forgive my indignation if this message comes to you as a surprise and if it might offend you without your prior consent and writing through this channel.

I am AYO MIKE,The Chairman, Contract Awarding committee of the ECONOMIC COMMUNITY OF WEST AFRICAN STATES ( ECOWAS)with Headquarters in Lome, Togo.

I got your contact through Network on line in my search for a reliable and reputable person to handle a very confidential transaction that involves a transfer of fund to a foreign account and I decided to write you.

After discussing my view and your profile with my colleagues,they were very much satisfied and decided to contact you immediately for this mutual business relationship.We wish to transfer the sum of USD 32m (Thirty-Two Million United States Dollars only.)into your personal or company`s bank account.

This fund was a residue of the over invoiced contract bills awarded by us for the supply of ammunitions, hard/softwares,phamaceauticals/medical items,light and heavy duty vehicles, apperals and other administrative logistics etc for the ECOMOG in Sierria-Leone and Liberia during the Peace Keeping Projects.

This DEAL was deliberately hatched out and carefully protected with all the attendant lope holes sealed off.As the Chairman of CAC,I have the cooperation and mandate of the Financial Director and the Secretary of the Organisation.We arranged and over invoiced the contract funds supplied by different companies from different countries during the crisis.

It was our consensus to seek the assistance of a willing foreigner to provide us with the facilities to transfer this money out of West Africa.This is borne out of our beleif in the non-stable and sporous political nature of this sub-region.

The original contractors have been duely paid by the Banque Centrale Des Etats De L`Afrique De L`Ouest (Central Bank of the West African States)through our bankers-INTERNATIONAL BANK OF AFRICA(IBA)UNION TOGOLAISE DE BANQUE(UTB),ECO BANK,BTCI BANK LOME TOGO.

This balance is suspended in the escrow accounts awaiting claims by any foreign company of our choice.We intend to pay out this fund now as the organisation is winding up its activities since the aim of returning PEACE to the countries and the coast has been achieved.

Based on the laws and ethics of employment,we as civil servants working under this organisation, are not allowed to operate a foreign account.

This is the more reason why we needed your assistance to provide an account that can sustain this fund for safe keeping and our future investment with your comprehensive advise,assistance and partnership in your country.

It is however agreed,as the account owner in this deal to allow you 30% of the entire sum as compensation, 65% will be held on trust for us while 5% will be usedto defray any incidental charges and cost during the course of the transaction.

This transaction will be successfully concluded within 14 days if you accord us your unalloyed and due cooperation.You should provide the followings:


Upon the receipt of this informations,i will forward them to the organisation for ratification and subsequent payment. As with the case of all organised (sensitive)and conspired DEALS,we solicit for your unreserved confidentiality and utmost secret in this business. We hope to retire peacefully and leave a honourable business life afterwards.There are no risks involved.

You can reach me through my private phone 00228 9321649.1 for more details.
With regards.

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