I just installed the update of Adrotate Pro and the update of W3 Total Cache to version 0.9.5. This caused a conflict which could only be solved by deactivating W3 Total Cache and deleting the object-cache.php file.
The website crashed and I could not access the admin area either. After deactivating W3 total cache via FTP I was able to access the admin area again and the website was working again as well. My question is: is there any known conflict between your plugin and W3 since the last updates.