Please tell us a little about your system. Right click "My Computer" and choose properties. What is the model and CPU speed and how much RAM do you have? What graphic card do you have and how much RAM does it have? What programs do you run? Does this happen randomly or only when you run certain things? Did this always occur? If not, when did it start happening?
Here are my info.
1. Model: Lenovo IdeaCentre B300
2. CPU Speed: Pentium(R) Dual-Core CPU E5400@ 2.70GHz
3. RAM: 2 GB
4. Graphic Card: Intel® GMA 4500MHD Graphics Card (RAM: 512MB)
5. Chipset: Intel (R) G41 Express Chipset (Microsoft Corporation - WDDM 1.1)
6. Programs I run: I don't quite get this. My problem no matter any program runs
7. It happens randomly but very often. But the programs could still run normally.
8. These problem happened after my mum open a document in her USB. But her document should be a normal one, not some spam files.