Hi there - I'm running windows 7 ultimate and have had no problems until a few days ago when the os stopped me installing software. The error message is 'These files can't be opened' 'Your internet security settings prevented one or more files from being opened' See Below... I've restored the computer to a previous date without success. I've run a virus scan which found 2 trojens and a malicious software. These have been removed. The main problem - apart from not being able to install any programs is that I cannot change the internet properties as some items appear barred (See Below...) - Has anyone seen this and can anyone help ??? I really don't want to format the hard drive and start again. Thanks in advance.