Board Thread:General Discussion/@comment-31579993-20170323003625/@comment-25615967-20170323105102

Uff there's a lot of things that can cause this error and not a real fix, this started on Chrome 53 and 54 and acording to the developers, the extension is disabled because it’s content doesn’t match the expected

I suppose you already tried clicking on repair, and that option just uninstalled and reinstalled the extension which didn't work, and I suppose you also tried uninstalling Chrome and installing it again, clearing cache and reinstalling the extension manually, so:

-Did you try to visit the extension page on the Chrome Web Store and click the enable button?

Now dragonjet the creator of the extension made a post sometime ago, but this was suposed to be fixed since 2015, well acording to him it has something to do with the alarm so you can try to remove 'alarm.mp3' from the folder:

https://github.com/KC3Kai/KC3Kai/issues/7

Also using local files as custom sound cause problems since Chrome detect that it's playing a file that is not part of the original extension, treating it as "corrupted"

If that still doesn't work:

-Reset chrome flags to default

-If you’ve played with chrome://flags/#extension-content-verification flag settings by setting as ‘Enforce Strict’, changing it to ‘Bootstrap’ worked for some

-You can also remove the unused permissions from the manifest file

-Chrome extension popups have a maximum height of 489px and maximum width of 800px So if the height went above those numbers that maybe corrupted the extension