Let's not suppose the worst yet (that's malware)
For the mouse problem, check the mouse settings in Control Panel. And try another mouse.
For the security problem, maybe http://www.google.com/search?q=%22SECURITY+WARNING%22+%22Do+You+Want+To+Open+This+File%22 finds a solution
Kees
Help! My desktop shortcuts have suddenly changed. Instead of opening the program with a double left click I now have to RIGHT click, then select OPEN. On a number of them I then I get s window called SECURITY WARNING that asks Do You Want To Open This File? Then when I click on Open, the program opens.
What setting(s) do I need to change to get back to normal (left double click opens)? I haven't been able to figiure it out. I am using Windows 7 Professional.

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