The side-by-side assembly privatization failed. You can find more information about the side-by-side assemblies in the Sequencer log file which is located in the following directory:
<App-V Sequencer installation drive> \Program Files \ Microsoft Application Virtualization Sequencer \ Logs
Install public versions of the required assemblies on the computer running the App-V Sequencer before you sequence the application. The same assemblies must also be installed on all computers running the App-V client before you deploy the package.