Dosen't work authentication with google or facebook

[maryampashmi]

Hi,
With my understanding from documentation i execute only grunt serve , but i am getting error 401 while i select google authentication or any others.
That’s an error.
Error: invalid_client
The OAuth client was not found.
I am not sure if i need to execute somethings inside server such as node app.js or not? it is not written in documentation anythings about server side. How i can solve problem of authentication?
or following error from twitter:

Error: Could not authenticate you. at Strategy.parseErrorResponse (C:\Users\pasma08\WebstormProjects\CspMetadata\node_modules\passport-twitter\lib\strategy.js:182:10) at Strategy.OAuthStrategy._createOAuthError (C:\Users\pasma08\WebstormProjects\CspMetadata\node_modules\passport-twitter\node_modules\passport-oauth1\lib\strategy.js:349:16) at C:\Users\pasma08\WebstormProjects\CspMetadata\node_modules\passport-twitter\node_modules\passport-oauth1\lib\strategy.js:218:41 at C:\Users\pasma08\WebstormProjects\CspMetadata\node_modules\passport-twitter\node_modules\passport-oauth1\node_modules\oauth\lib\oauth.js:543:17 at passBackControl (C:\Users\pasma08\WebstormProjects\CspMetadata\node_modules\passport-twitter\node_modules\passport-oauth1\node_modules\oauth\lib\oauth.js:397:13) at IncomingMessage. (C:\Users\pasma08\WebstormProjects\CspMetadata\node_modules\passport-twitter\node_modules\passport-oauth1\node_modules\oauth\lib\oauth.js:409:9) at IncomingMessage.emit (events.js:129:20) at _stream_readable.js:908:16 at process._tickCallback (node.js:355:11)

However i don't get this error through demo at all. I am getting error while using http://localhost:9000

Moreover in part of app.js inside server folder i am getting error from line exports = module.exports = app; after removing first exports, error disappear. Is that fine to remove first exports?