I'm developing an android xamarin app in c#. When I test or create the app, I receive the following error:
C:\Program Files (x86)\MSBuild\Xamarin\Android\Xamarin.Android.Common.targets(2,2): Warning: No -tsa or -tsacert is provided and this jar is not timestamped. Without a timestamp, users may not be able to validate this jar after the signer certificate's expiration date (2044-03-30) or after any future revocation date. (App3)
I tried to download the last version of java but it doesn´t work.
You have signed your app with a certificate that expires in 2044-03-30. That's ok.
But it's warning you that if you want your users to verify/validate this app after 2044-03-30, you should use a timestamp when you sign your app.
It's a long expiration, it is common to expire in less time, you don't need to concern too much about it.
These links should help you with more support about timestamping.
https://support.comodo.com/index.php?/Default/Knowledgebase/Article/View/68/7/ https://stackoverflow.com/a/24178906/396200