I just download the latest version and set it up. When I try to login using Facebook Connect I get the following error.

2. Facebook SDK returned an error: Cross-site request forgery validation failed. The "state" param from the URL and session do not match.

I am running this on another site that requires a login. Even though I'm not logged into that area could it still be a session thing?

On Facebook under the advanced settings for the app, does something have to be set for Web OAuth Login or does it need to be turned off?

I have the following setting:

Visit Link: http://buildmybiz.in/fb%20advance%20setting.PNG

Same error for me. I have applied ithe same settings that you have on your side also.

Are you running your webserver on localhost or some other server that is not registered to your facebook App?

The exception mentioned above occurs while trying to get the accesstoken from facebook. So the possible reason for the error might be:

1. Facebook "key" or "secret" might be wrong.
2. You might have configured something wrong in your app.
3. You might have configured everything correctly but trying to call it via some other domain.

Found a possible fix from stackoverflow:

Enable WebAuthLogin under the advanced tab. Provide the url in the WebAuthLogin settings as same as that which is provided in getLoginUrl function.For this what you need to do is, if your domain is http://example.com/ use "http://example.com/facebook_connect/login" in the WebAuthlogin Url.

Following are the possible domain name and its respective WebAuthLogin URL

Note: make sure that you have taken into consideration the "www" and "non-www" part of the domain.

I'm not running on localhost.

I copied and pasted the id and key.

I verified the site url but might have the WebAuthLogin URL incorrect.

I'm getting the same error message. The domain is simple. I have my settings per your screenshot. The only difference is my elgg isn't in the root but a directory.

While I get the error it does log me into Facebook.

Which elgg version are you using?

Which php version are you using, I just came to know that facebook SDK requires PHP 5.4 or greater.

If you are still getting the error. Try the new source code at https://github.com/rohit1290/Facebook-Login-1.9-1.12 and check if this has resolved the issue or not.

Im not seeing any facebook icon/Button at login page....?

With or without theme.... 

I'm running php 5.4.

I downloaded the version from github and activated it. As soon as I logged out I got this error.

I've deleted the plugin and will see if I can get my site to come back up

Ok, the error is at the time of logout right? that means you can now login.

Can you check the error_log file and tell me what was the Error from the log file.

@Juanduino.. what is your site link? try "Flush the caches" and then "Upgrade"

Where is the error_log file so I can check it? I checked the root of my /elgg installation and didn't see it there. If it is in the /facebook_connect folder I deleted that folder in order to get my site to come back up.

@Dan, can you check if you have any error log file in the engine folder and if the logs for the above exception is available there.

@Rhohit, there isn't any log in the /engine folder.

I still have the same issue .. not able to make it work. I have tried what Rohit Gupta told us to do. But still having the same issue.

2. Facebook SDK returned an error: Cross-site request forgery validation failed. The "state" param from the URL and session do not match.

The parameters on my facebook application seems to be just fine but not working.

Yes i am running on the localhost on a Linux Server. But it is running into the /var/www/elgg

So on my URL it's : https://DOMAIN/elgg/facebook_connect/login

I'm wondering if it has something to do with the fact that we have our elgg installations in a sub-directory and not it the / (root)?

What I can see is both of you (Dan and Edve) have installed your elgg somewhere other than the root directory. Probably the issue might be due to this, that the plugin only work for elgg which are installed at root folder. I have only rewritten the "lib/facebook_connect.php" file of facebook connect for 1.8 so that it is compatible with the latest facebook APIs.

Give me some time.. let me analyze the rest of the code so that I am in a better position to resolve the issue if this is the case.

Meanwhile, Is there anyone else here who has their elgg in some other directory and facing the same issue?

Ok i got the icon showing... But i get the { Cross-site request forgery validation failed, error. } On a clean and fresh non subfolder 1.12.4 Elgg install. 

Thats with the plugin from here, the one from repository throws fatal error at me :\ 

Thanks Rohit , I'm gonna make a try on putting it on my main webserver root directory.

http://www.campux.dk/eaaa/

It doesn't work for me. It says the user name / password isn't correct and it is. I verified it and typed it in carefully.

Hi Juanduino, I saw your website. You are not using this plugin on your website.