ClassNotFoundException for SignInConfiguration when signing in with Google

Question

I\'m implementing Google login to an app. The login itself seems to work okay, but the moment I request either the user\'s e-mail or ID token I see the following stack trace

Answer 1

I got this issue fixed in this way: I deleted my project the google developer console, and created another one with a different name, also I changed my package name almost completely: for example from com.example.android.appname to com.y.android.anothername. Then I generated signed apk with my previous certificate and google signing worked without giving me that error.

Answer 2

I think this might be a red-herring. I had the exact same stack trace and have spent a ton of time trying to determine the cause. I came across a similar post while researching which indicated it might be a Samsung only exception that could be ignore (them inspecting intents in transit or something). Sure enough, I tried on an HTCOne device and the exception no longer appeared. I still had the same overall Google Auth problems, but at least I could move on to the real issue which (for me at least) appears to be SHA/Cert/Account/Signing related. Anyway - hope this helps (something to check on anyway)

Answer 3

I solved my problem by putting "App signing Key" to OAuth 2.0 Client ID SHA-1 finger print instead of signed key which was generated by using keytool. If you have checked "Google Play App Signing" in Google Play Console, the usual signed key will not work. Check out your App signing Key in Google Play Console>App signing>App signing certificate and then copy SHA-1 certificate fingerprint and paste to Google API console OAuth 2.0 Client ID. It worked for me!