I found that this stackoverflow post had some correct and some slightly misleading comments. The following worked for me.
- In Android Studio select Build, Generate signed APK and navigate to the release key previously used in Eclipse.
- Enter your keystore password.
- Click on the small box to the right of alias and select your key alias. If the password was not correct in the previous step then you will see a message suggesting the keystore is corrupted. Change the password and try again.
- Enter the same password again as the key password.