you'll need to re-package the .apk to run on the emulator. I haven't figured out how to do it through the gui. the command-line for that is:
adt -package -target apk-emulator -storetype pkcs12 -keystore mycert.p12 TestMobile01.apk TestMobile01-app.xml TestMobile01.swf
you'll find adt in Adobe Flash Builder Burrito\sdks\4.5.0\bin\ folder
Do you have AIR 2.5 installed on your emulator?
Yes, Air 2.5 is installed on emulator.
I also tried to install the application over htc desire hd (android 2.2) and I get the same error...
I tried a very basic Android app with Burrito, just the homescreen and a button.
Same error "Application not installed".
Then I created another very basic Android app with Flash CS5 and Air for Android.
No errors...emulator and device install it correctly and it runs.
...can't figure out where the problem is...