Failure [INSTALL_FAILED_UPDATE_INCOMPATIBLE]

Hi,

I'm getting the following error when trying to deploy to my Nook HD+ running CyanogenMod (ovation 10.2.1 - Android 4.3.1).

Detecting installed packages

Waiting for packaging to complete

Removing previous version of application

Installing application on device

Deployment failed because of an internal error: Failure [INSTALL_FAILED_UPDATE_INCOMPATIBLE]

Deployment failed. Internal error.

Running on this system used to work before Xamarin 5.0. Is there something I can check to see why this is saying it is incompatible? It does this in all modes - debug, release and it also fails while manually installing a published apk.

Thanks,

Kevin N.