Firstly, lets see if there are some key system files that Windows thinks should be repaired.
Follow these steps:
1. Click Start Orb.
2. In the search box, type cmd
3. Right-click on the cmd option in the list that appears after step 2, and then select "Run as administrator".
4. In the cmd window that appears, type sfc /scannow and hit enter
Post the results that appear when the process finishes (it can take some time depending on your system).