How to solve : "Unsupported class version number[52.0] maximum 51.0, Java1.7"?

Question

Can't read

[C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\MonoAndroid\v7.0\mono.android.jar] (Can't process class [android/app/ActivityTracker.class] (Unsupported class version number [52.0] (maximum 51.0, Java 1.7)))

how to solve this issue..??

Possible duplicate of [Unsupported major.minor version 52.0 in Visual Studio + Xamarin](http://stackoverflow.com/questions/39879486/unsupported-major-minor-version-52-0-in-visual-studio-xamarin) — Prashant Cholachagudda, Oct 13 '16 at 06:39
Possible duplicate of [Error Proguard Unsupported class version number](http://stackoverflow.com/questions/22670059/error-proguard-unsupported-class-version-number) — jdstaerk, Oct 13 '16 at 12:04

jdstaerk · Answer 1 · 2016-10-14T06:08:08.653

3

Had this error too. Which JDK Version do you have installed? I had no problems after upgrading it to version 1.8

Alright, if somebody else is reading this with the same problem, upgrading ProGuard seems to fix this problem too. Just try that! :)

edited Oct 14 '16 at 06:08

answered Oct 13 '16 at 06:08

jdstaerk

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I am using jdk1.7.0_55 – Santhoshkumar Polu Oct 13 '16 at 06:48
Just try what I suggested, it worked for me. Install JDK version 1.8 and set in Visual Studio / Xamarin studio – jdstaerk Oct 13 '16 at 07:10
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The latest version of Android build tools require you to install JDK 1.8 – Prashant Cholachagudda Oct 13 '16 at 07:53
ERROR-Can't read [C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\MonoAndroid\v7.0\mono.android.jar] (Can't process class [android/app/ActivityTracker.class] (Unsupported class version number [52.0] (maximum 51.0, Java 1.7))) – Santhoshkumar Polu Oct 13 '16 at 11:58
Did you also added the new jdk in visual studio (Tools -> Options -> Xamarin)? And try to clean + rebuild project – jdstaerk Oct 13 '16 at 12:00
Yeah I know. But just installing isn't enough. Did you added it in Visual Studio? Did you tried my steps I suggested in my last comment? Please provide more information and complete sentences if you want more help. – jdstaerk Oct 13 '16 at 12:03
every time clean and rebulid the project – Santhoshkumar Polu Oct 13 '16 at 12:06
i am also add jdk 1.8 in visual studio – Santhoshkumar Polu Oct 13 '16 at 12:08
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Thank u for ur responce..Actually the problem is ProGuard version. it does n't support jdk 1.8 after installing the latest version ProGuard 5.3 it's working.. – Santhoshkumar Polu Oct 14 '16 at 05:13

How to solve : "Unsupported class version number[52.0] maximum 51.0, Java1.7"?

1 Answers1