Warning: Cannot find parent tsconfig.json

Try setting up include section in file tsconfig.json like in below image.
(Note that my project's root folder is frontend and my include section is frontend/**/*).

Of course you don't need to rename your project's root folder to frontend.
Only the naming should match.

It should take effect immediately after you save the tsconfig.json and open a .ts or .tsx file. If it doesn't try restarting the WebStorm/IDEA.

And don't forget to clear the error console before testing this solution. It might cache the previous messages.

P/S: I'm using WebStorm 2016.3.1.

If you were using webpack together with ts-loader the above solution would cause your builds to fail. If that was the case consider this approach instead.

problem is specific to TypeScript version being used (2.1.x); it is fixed in 2016.3. 2 EAP

Note: this answer refers to the issue specific to IDE (WebStorm, PHPStorm, IDEA) version 2016.3: it didn't work well with TypeScript 2.1.x, showing false warnings.If you see similar message (Cannot find parent tsconfig.json) in other IDE versions, it is likely a problem with your configuration: such messages are displayed if currently edited .ts file is not included in any tsconfig.json.

None of the above solutions worked for me, but I did stumble onto a tsconfig change that did. It seems the IDE is using different rules that tsc.

This did NOT work:

"include": ["./typings", "./src", "./test"],

This did work:

"include": ["./typings/**/*", "./src/**/*", "./test/**/*"],