Hi,
Thank you for posting the query on Microsoft Community.
I am sorry to know that you are unable to open anything on the computer.
- Which anti-virus program are you using?
- Do you get the same error when you try to use a browser and a Media Player?
I suggest you to try the steps provided by Waseemulla Shariff in the link below and check if it helps.
For MS office, you need to post the query on Office forum.
http://answers.microsoft.com/en-us/office
Please get back to us with the results to assist you further.