I have work with Magento 184.108.40.206 in Ubuntu OS, my one of the colleagues work with the same project in Window 7 OS,i am newly configured my project in Ubuntu OS
when i login via the backend it show me the error "Invalid Form Key. Please refresh the page".
But for my colleagues its working well.
My localhost URL : 1) localhost/workspace/magento/index.php/admin 2) mylocalip/workspace/magento/index.php/admin
When i use the second link for admin login there is no issue, but with the first link only throw the error.
For your more information, i was installed the apache2,PHP,Mysql and phpmyadmin.
Thanks advance for your idea.