I purchased Bitdefender 2012 on the basis it had received the best reviews. I received the Cleverbridge reciept and the download details. All went well on first machine. I then tried to install on second machine (3PC Licence version purchased) and after the AVG software had been uninstalled I kept being told I had corrupted files when trying to install the new Bitdefender and to download a new version. I tried this several times without success. I did get the box to insert the licence number and email address. It said the licence number was not valid. I now have a laptop which has no security protection. Help!!!