Clearly there are many causes of this problem. For me the situation was this: I had deployed to my nexus 7 (actual device) from within the Android Studio (v1.3.2). All worked fine. I then created a signed apk and uploaded to my Google Drive. After disconnecting my nexus from the usb, I went to the settings/apps and uninstalled my app (App1). I then opened google drive and clicked on my App1.apk and chose to install it (need to ensure you have allowed installation of apks in settings). Then I got the dreaded message "App not Installed"

Solution for me: go back into settings/apps and scroll though all apps and at the bottom was a pale version of my App1 (note the original App1 was at the top in Alphabetical order which was deleted as above). When clicking on the pale version it said "Not installed for this user". (I had set up my nexus to have more than one user). But in the top right corner there is a three dot button. I pressed this and it said "Uninstall for all users". Which I did and it fixed the problem. I was now able to click on App1.apk and it installed fine without the error.

我有同样类型的错误，这是由我的android manifest XML文件中的这一行引起的。

android:permission="android.permission.INSTALL_LOCATION_PROVIDER"

我去掉了那条线，问题就解决了。希望这能有所帮助

Clearly there are many causes of this problem. For me the situation was this: I had deployed to my nexus 7 (actual device) from within the Android Studio (v1.3.2). All worked fine. I then created a signed apk and uploaded to my Google Drive. After disconnecting my nexus from the usb, I went to the settings/apps and uninstalled my app (App1). I then opened google drive and clicked on my App1.apk and chose to install it (need to ensure you have allowed installation of apks in settings). Then I got the dreaded message "App not Installed"

Solution for me: go back into settings/apps and scroll though all apps and at the bottom was a pale version of my App1 (note the original App1 was at the top in Alphabetical order which was deleted as above). When clicking on the pale version it said "Not installed for this user". (I had set up my nexus to have more than one user). But in the top right corner there is a three dot button. I pressed this and it said "Uninstall for all users". Which I did and it fixed the problem. I was now able to click on App1.apk and it installed fine without the error.

主要针对老款手机

我只是在试图在我的手机上安装一个运行在4.4.2(又名奇巧)上的apk时遇到了应用程序未安装错误，但我的朋友在他的手机上运行在6+上时没有遇到这个错误。我尝试了其他解决方案，比如删除旧的/调试版本的应用程序(因为apk是一个发布版本)，清除调试应用程序的数据，甚至清除我所有的缓存数据。然后，最后我意识到我所要做的就是在构建我的签名apk时选择两个签名版本。

之前我只选择了V2(完整的APK签名)，但在选择V1 Jar签名之后，我能够成功地在4.4.2设备上安装我签名的APK。

我知道这是一个老帖子，但对新用户可能有用。我也遇到了同样的问题:我的应用程序在调试时工作得很好。当我签署APK时，我得到了同样的消息:“应用程序未安装”。

我修复了卸载JDK(我使用的是JDK -6u14-windows-x64)并安装了一个新的JDK (JDK -6u29-windows-x64)。导出并再次签署APK后，一切正常!

恢复，我的问题是在JAVA版本。谢谢的甲骨文! !

如果你在AndroidManifest.xml中声明了两次MainActivity，就会发生这种情况。

另一个可能的原因是:您更改了启动活动。提示:永远不要对已经发布的应用程序这样做!原因在Android开发者博客中讨论过。