Sourceforge offers NetChecker which is a free Internet connection checking program.
“NetChecker is a simple text based software to check internet connectivity problems. Netchecker can detect most common connectivity problems of wired and wireless broadband internet. NetChecker will first identify the exact problem preventing computer from accessing the internet and then if possible it will also try to resolve the problem.
NetChecker uses Windows shell utilities which come preinstalled with Windows. Netchecker does not use any third party tools and hence it is fast, safe and reliable. Netchecker is designed and tested to run on Windows XP, Windows Vista, Windows 7 and Windows 8.
NetChecker won’t work on Windows versions prior to Windows XP.
NetChecker currently can test and fix problems of most types of wired and Wireless broadband connections. Mobile internet and Dial-up connections are not supported.
NetChecker does not contain any spyware, malware, adware. NetChecker is completely free.”
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