Did you try to open multiple apps? I believe your system has Windows 8 installed. If you have turned off User Account Control, your Metro apps will not work.
You can check if UAC is enabled here:
In case the issue stll persists, you can Refresh your PC:
Note: Your files and personalization settings won't change. Your PC settings will be changed back to their defaults. Apps from Windows Store will be kept. Apps you installed from discs or websites will be removed. A list of removed apps will be saved on your desktop.
Then follow the instructions that will be provided on the screen to refresh your PC
Keep me posted. Please reply for any further questions.
Thanks and Regards,
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