diff --git a/lib/galaxy/model/__init__.py b/lib/galaxy/model/__init__.py
index 12d39564e6e..adbe7a2fcbb 100644
--- a/lib/galaxy/model/__init__.py
+++ b/lib/galaxy/model/__init__.py
@@ -3630,11 +3630,6 @@ class ToolShedRepository( object ):
             return galaxy.util.asbool( self.tool_shed_status.get( 'repository_deprecated', False ) )
         return False
 
-    @property
-    def is_installed( self ):
-        return self.status in [ self.installation_status.DEACTIVATED,
-                                self.installation_status.INSTALLED ]
-
     @property
     def is_latest_installable_revision( self ):
         if self.tool_shed_status:
diff --git a/lib/tool_shed/galaxy_install/tool_dependencies/install_util.py b/lib/tool_shed/galaxy_install/tool_dependencies/install_util.py
index 607feaf26b6..c9cbd0fd8e7 100755
--- a/lib/tool_shed/galaxy_install/tool_dependencies/install_util.py
+++ b/lib/tool_shed/galaxy_install/tool_dependencies/install_util.py
@@ -98,9 +98,9 @@ def create_tool_dependency_with_initialized_env_sh_file( app, dependent_install_
                                                                                                               tool_dependency,
                                                                                                               error_message,
                                                                                                               remove_installation_path=False )
-                        elif required_tool_dependency.in_error_state:
-                            error_message = "This tool dependency's required tool dependency %s has status %s." % \
-                                ( str( required_tool_dependency.name ), str( required_tool_dependency.status ) )
+                        elif required_tool_dependency is not None and required_tool_dependency.in_error_state:
+                            error_message = "This tool dependency's required tool dependency %s version %s has status %s." % \
+                                ( str( required_tool_dependency.name ), str( required_tool_dependency.version ), str( required_tool_dependency.status ) )
                             tool_dependency = tool_dependency_util.handle_tool_dependency_installation_error( app,
                                                                                                               tool_dependency,
                                                                                                               error_message,