Hi,
I can understand how frustrating it can be when things don’t work as expected. I'd be glad to assist you with this issue.
Please provide us certain information to narrow down the issue:
- What is the make and model of your computer?
- To which account are you logged in to your Windows 8.1 ? Is it an “Administrator” account?
- Do you suspect any malicious software infection on the computer?
- What are the recent changes that you have made on the computer prior to this issue?
If you suspect any malicious software infection on the computer, then I would suggest you to perform a security scan using Microsoft Safety Scanner and check if that resolves the issue. You may follow these instructions for the same.
The Microsoft Safety Scanner is a free downloadable security tool that provides on-demand scanning and helps remove viruses, spyware, and other malicious software. It works with your existing antivirus software.
http://www.microsoft.com/security/scanner/en-us/default.aspx
Note: The Microsoft Safety Scanner expires 10 days after being downloaded. To rerun a scan with the latest anti-malware definitions, download and run the Microsoft Safety Scanner again.
Note: Any data files that are infected may only be cleaned by deleting the file entirely, which means there is a potential for data loss.
From the information which you have provided, there seems to be issue with the Default Gateway as it says Default gateway not available.
I would suggest you to refer to the suggestion from HirenParekh replied on February 24, 2014 and check if it helps.
Hope this information is helpful. Please do let us know if you need further assistance, we’ll be glad to assist you