Hello László, I'm Greg, here to help you with this.
I understand you're having problems installing Java, and have an error which means there's a bug in the Store.
- First let's deal with the error fixes here:
https://windowsloop.com/fix-you-need-a-new-app-...
https://helpdeskgeek.com/windows-10/fix-youll-n...
https://www.youtube.com/watch?v=tbLuiod9ESE
- Once that's fixed here are fixes for Java won't install:
https://bottobotto.com/java-wont-install/
https://www.techrepublic.com/article/10-things-...
https://techshift.net/how-do-i-fix-java-unable-...
https://www.youtube.com/watch?v=Vt9-jKNsH3E
Feel free to ask back any questions. Based on the detailed results you post back, I will have other suggestions if necessary.
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