对我来说，在Android 9 (API 28)上，从播放商店应用程序中禁用谷歌播放保护起作用了，我能够摆脱应用程序未安装的错误。

禁用谷歌播放保护功能。打开“Play Store”应用=>点击 on菜单按钮=> select "Play Protect"选项=>禁用选项 “扫描设备安全威胁”。

我的问题是:我使用了调试Apk，这是在我从Android Studio执行Run命令时生成的

解决方案是:不使用此文件，清除项目并单击Build > Build APK(s) from Android Studio。然后你可以使用生成的APK从通常的文件夹(app/build/outputs/ APK /debug/)

像这样生成的文件安装起来没有问题。

我发现，如果我用compileSdkVersion构建我的应用程序，buildToolsVersion和targetSdkVersion都设置为默认值30在我的构建。Gradle文件，那么应用程序将无法安装在我的手机上。但是，如果我把它们改回版本29，它就可以工作了。问题是，从SDK 30开始，你需要选择V2 jar签名。有关更多信息，请参阅为什么Android SDK 30生成无效的APK文件?

确保考虑到以下建议:

Your build variants and Flavors should be same(App installed and new one), usually release Signature file must be the same(*.jks file) The version you set in build.gradle or AndroidManifest have greater value compared to current version(it is recommended to set version in build.gradle) URL is correct(doesn't have typo) and server is reachable(WebService/WebMethod/WIFI is running/available and ...) File downloaded completely File saved correctly into desired directory Setting for Data and Type in setDataAndType is correct

我今天遇到了类似的问题，起初我以为是我的sd卡损坏了它。我在许多运行android 4.4及更高版本的设备上尝试了它，但它一直带来同样的问题。经过一些谷歌和研究，我意识到我没有选择v1 jar签名，这是设备比android 7.0牛轧糖，所以我应用了这两个签名，通过选择两个复选框，并生成了一个签名的apk，它工作。

链接到解决方案Android -应用程序未安装错误时，安装签名APK -如何修复

I had a similar situation.I was able to install app in debug mode using USB but not a signed version. I was able to install signed version on other phone, but not on my device. Numerous reasons and solutions did not help me. But one direction I got from a solution "uninstall for all users". What I did is to again install app in debug mode using USB connection, go to app details and "uninstall for all users" from right top 3 dots - to remove debug version. This looks like cleared all kinds of references. I usually do a normal uninstall.

现在我能够在设备上获得签名APK并成功安装。