'App not Installed' Error on Android

Question

I have a program working in the Android Emulator. Every now and again I have been creating a signed .apk and exporting it to my HTC Desire to test. It has all been fine.

Answer 1

create keystore file through command line

keytool -genkey -alias key_file_name.keystore -keyalg RSA -validity 1000000000000000 -keystore key_file_name.keystore

export apk through Eclipse, right click on Android project Android Tools > Export Signed Application Package, then give keystore location & password.

this will crate signed apk at the same time apk will be zipaligned. And installable.

If you go through command line for all, some times you may face "Application not installed" error. (Application not installed error can happen not only, when using command line. It can be some other reasons as well)