I am using Windows 7 64 bit. In the last few weeks I have had problems opening some files downloaded from the internet. These are standard files from well-known reputable sources. The latest is Firefox setup 28.0.exe . (I thought my browser Chrome might be causing the trouble)
Others are fdminst.exe, Virtualbox-43.4-91207win.exe and Avast-browser-cleanup.exe.
I click and get the usual message Run or Save. I click Run and get the error message ""Cannot open File C:\stuart\appdata\local\temp\filename .tmp". Sometimes the message has The name 7Zip as the title. I never use 7Zip and don't have it installed. The error messages vary slightly - even for two attempts at the same file! But are always about the same sometimes with Access Denied.
There are no other users.
Have I got a virus? I use AVG and also periodically Malwarebytes Anti-Malware but they have found nothing.
Finally I have downloaded some other files and have opened them with no difficultyy.
Can anyone help ?