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- I lost my .keystore file? 11 answers
I've seen a lot of posts about losing keystore passwords, but I have my keystore password but lost a private key password. Now, I can't sign using that key, which is required to update my app. Is there anything I can do?
No, there is nothing you can do.
The apk must be signed with the exact same keystore and profile within the keystore. You cannot simply generate another one with the same password and details. It will not work.
You will have to publish your app again with a new keystore and under a different package name, or remember your password.
来源：https://stackoverflow.com/questions/15635974/have-keystore-password-lost-key-to-sign-android-app