Failure INSTALL_FAILED_MEDIA_UNAVAILABLE
I've installed JDK, Android SDK and Mono Android for Visual Studio 2010, I've created an empty solution and I got the emulator up and running with Android 2.3.3 - so far so good.
When I try to deploy (F5) the app to the emulator, it connects to the emulator, and all goes fine until it starts "Installing the platform framework". Then it loads for several minutes, and finally throws an exception that looks like this:
I have tried googlin' it, but the INSTALL_FAILED_MEDIA_UNAVAILABLE doesn't seem to be described anywhere else.
I don't know if this is an important detail, but on my PC I have remapped my home folders (Documents, Favorites, Desktop, etc.) to folders like "D:\Mikkel\Dokumenter". It seemed to cause some problems when starting the emulator initially, but after adding the environment variable "ANDROID_SDK_HOME" pointing to "D:\Mikkel.android" the emulator started up with no problems.
Please advise.
Answer
Ensure that you have enough internal and external free space in your device. You can determine the free space available with the command:
$ adb shell df
Filesystem Size Used Free Blksize
/dev 192M 32K 192M 4096
/mnt/asec 192M 0K 192M 4096
/mnt/obb 192M 0K 192M 4096
/system 145M 124M 20M 4096
/data 196M 167M 29M 4096
/cache 95M 32M 62M 4096
/mnt/sdcard 3G 177M 3G 32768
In the above output, /data (which is the default install location) has 29MB free, while /mnt/sdcard (the SD card, and the external install location) has 3GB free.
For Debug builds, you need to have ~40MB free (for the Runtime package, Platform package, and apps). Release builds are significantly smaller, but Release builds cannot be created with the Evaluation version.
It's plausible that if your emulator doesn't have an SD card, then Android would generate the INSTALL_FAILED_MEDIA_UNAVAILABLE error. (To add an SD card to your emulator, start the android app, go to Virtual devices, select a device, click Edit, and look at the SD Card section.)
A cursory grepping of Android suggests that DefaultContainerService.java is the controlling factor, specifically DefaultContainerService.recommendAppInstallLocation(), and that if you're out of internal space and the package specifies auto (as Mono for Android does) and the SD card is unavailable (status.equals(Environment.MEDIA_MOUNTED) is false), then RECOMMEND_MEDIA_UNAVAILABLE is returned, which is translated into INSTALL_FAILED_MEDIA_UNAVAILABLE. This still seems odd to me (wouldn't RECOMMEND_FAILED_INSUFFICIENT_STORAGE make more sense?), but this appears to be what's happening.