• Hello [name]! Thanks for joining the GMC. Before making any posts in the Tech Support forum, can we suggest you read the forum rules? These are simple guidelines that we ask you to follow so that you can get the best help possible for your issue.

Android Certificate problem porting an old app to GM

Josepho

Member
Hi friends, i did in the past 2014, a game using adobe air and after watching the dawn of flash i decided to port it to game maker, everything looked to work perfectly, im using the original keystore (thats its a p12 file) and game maker generate the apps without any issue.

The problem has come now when i have tried to update the app with the new version done in gm, in a device in which the old version exists. It says there is a certificate conflict.

If i try to push it in the internal test system of google play it displays this error.
No APK Signature Scheme v2 signature from this signer ERROR (APK Signature Scheme v2 signer #0): No JAR signature from this signer

Do you know what can i do in order to fix this?

----------------------------

Ok, nobody has replied but after 2 days of research i think i have been able to fix everything. As in 2020 adobe will stop updating air and as probably more devs like me are going to have a bad time moving to other enigines here is how i did it.

As I suspected te p12 keystore is the main issue, if you pass it to jks it loses its fingerprint, so the way to sign the app its has to be done the following:

- Step 1: Generate the apk with game maker
- Step 2: Rename the apk to .zip
- Step 3: Remove the META-INF folder and rename it again to apk
- Step 4: Use the jarsigner tool in jdk folder to sign the app, the line is this one in the cmd
jarsigner -keystore file.p12 -storepass mysecretpassword pkcs12 myapp.apk myalias
- Step 5: You need to zip align the result using the zip align tool in java as well
zipalign 4 myapp.apk myapp-aligned.apk

This will generate a new apk the "-aligned" one that its supposed to work

The key is that the new fingerprints needs to match with the adobe air apps in order to watch the fingerprint of an apk you need to unzip it, pick the RSA fle inside META-INF and use this command line
keytool -printcert -file CERT.RSA

As its a pain to do this everytime you want to compile i hope yoyo implements some kind of build commands in the future, meantime you can create a .bat that makes the work every time you build
 
Last edited:

chirpy

Member
My 2 cents would be to contact Google Play console support; they may be able to do something for you from the back end to resolve the fingerprint issue for good.
 

Josepho

Member
They have told me to upload a new app and remove the old one :( im a bit pissed they didnt gave me the solution i found it in a lost blog way hidden on the internet
 
Top