Adb Install Failure INSTALL_FAILED_VERSION_DOWNGRADE

Question

I uninstalled whatsapp and kept its data using:

adb.exe shell pm uninstall -k com.whatsapp

Then I tried to install an old version of whatsapp, but got the following error message even using the -r -d flags:

>adb install -r -d tmp\LegacyWhatsApp.apk
1738 KB/s (18329558 bytes in 10.298s)
Failure [INSTALL_FAILED_VERSION_DOWNGRADE]

I'm using Windows 10 and Pixel XL android version 7.1.2

Answer 1

Since Android 7 (Nougat), for security reasons, packages can no longer be downgraded unless they are marked as debuggable. Quoting the commit message :

An attacker could downgrade a package to an older version with known security vulnerabilities and then use some of the vulnerabilities to access the application's data. This would constitute a bypass of Android Application Sandbox. Thus, downgrading while keeping application data is no longer permitted.

You must uninstall it completely.