Unable To Create Android Oauth2 Client Id (duplicate Fingerprint)

When creating a client ID for Android in the Google Cloud Platform developer console, I get the following popup: Duplicate fingerprint The fingerprint you specified is already use

Solution 1:

First why we need to have an unique cert and package name.. A while back we decide that you shouldn't need to specify clientID in the android app (for dev simplicity and mitigate certain issues e.g. someone can not claim/use your client id if they don't have the cert even if they can have the same package name). We can do a lookup the clientID based on the package name and cert hash. This requires the combination to be unique. Does that make sense? To be clear you can use the same cert along with a different package name of the app and many do.

Is it a best practice to always use a new release signing certificate for every Android app?

I think there are pros and cons. If you ever want to sell/change ownership an app (out of many you have), it would be easier with separate cert. Also you need to think about the compromise or loss of cert. Same cert does make release process easier and to claim that they are from the same entity.

Solution 2:

just create a new project with a different package name