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^^ Go through everything in your task list and check it off that list.
Also go to Start>>Run, "msconfig">>Startup tab - check what's being launched at startup.
You say you haven't changed anything in your system. Check system restore to see if a restore point has been set which might coincide with the start of the problems you've got.
Make sure you antivirus software is set to do a FULL system scan. They normally don't, by default.
^^ Go through everything in your task list and check it off that list.
Also go to Start>>Run, "msconfig">>Startup tab - check what's being launched at startup.
You say you haven't changed anything in your system. Check system restore to see if a restore point has been set which might coincide with the start of the problems you've got.
Make sure you antivirus software is set to do a FULL system scan. They normally don't, by default.