More detail about the problem.

I am able to click on the facebook importer icon and select friends to send the request, however, when the friends try to open the link to my site, it shows the following screen:

And I also get an email from facebook:

TAK YEUNG, sorry for the delay in replying to you.
Is this issue still relevant?

yes. The facebook contact importer was not working. I've taken the plugin off my site until it's been fixed. thanks

You are the first one to report this.
We recommend one of the following options:

1. Delete your current APP, create new one. See whether it get's blocked again.

2. "Bring a core element".
Edit facebook_canvas.html ( ow_plugins/contact_importer/views/controllers) so that it contains more data.

Facebook not working neither.

Jabid, please provide more details on what is not working. Screen shot of your App's settings on Facebook will help a lot as well.

Not working.

Daniel, please provide your site URL and admin panel username/password in PM.

FB importer is not working on IE and Chrome, when I click the button, nothing happens and no pop-ups...but it does work on Waterfox...hope you can help

Ron, screen shot of your App's settings on Facebook will help a lot as well.