wIf you go to the Turn Off the Lights Chrome web store and click on the install button, some users see this message about a network connection is failed “NETWORK_FAILED”.
That is a known issue from the Chromium. Only some users receive this error message in his Google Chrome or another Chromium browser. Many users have reported that uninstalling and reinstalling Chrome resolves this issue.

NETWORK_FAILED
Latest update from the Chromium Team on 2 December 2014:
At this point we’re pretty sure that this error is primarily caused by malware / unwanted software on your machine actively tampering with the contents of the chrome binary and your user profile directory data. Some of the common ways we see people ending up with this kind of unwanted software is that it is bundled with the install of some other “free” native software like bittorrent clients, download managers, registry cleaners, screensavers, or in non-authoritative installers (eg a skype installer that doesn’t come from skype.com).
These ride along programs often make money for their authors by changing your chrome new tab page and/or search provider to something you didn’t want, installing extensions which inject/replace ads on web pages, etc. So a note on the steps people have posted to fix this: reinstalling chrome seems to be at least a temporary fix, although if you don’t remove the unwanted software that tampered with chrome then you may end up having the same problem again.
There is a pretty limited amount we can do within chrome itself when our code is literally being changed out from underneath us by another program that has the same or greater privilege level as chrome. We are working on a separate experimental unwanted software removal tool (https://www.google.com/chrome/srt) that can fix some problems, but unfortunately I don’t think currently fixes this one. Perhaps in the future it will. Any users affected may also want to try contacting vendors of antivirus/antimalware tools you use to see if they can add detection of the kinds of tampering mentioned in comment 105 on this bug.
I’m going to close comments to non-chromium project members on this bug since the appropriate place to have discussions about NETWORK_FAILED is at the Chrome community help forum.
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