diff --git src/bp-core/bp-core-taxonomy.php src/bp-core/bp-core-taxonomy.php
index 69932c953..fc0597ad0 100644
--- src/bp-core/bp-core-taxonomy.php
+++ src/bp-core/bp-core-taxonomy.php
@@ -167,7 +167,10 @@ function bp_get_object_terms( $object_ids, $taxonomies, $args = array() ) {
 		}
 
 		$site_terms = wp_get_object_terms( $object_ids, $site_taxonomies, $args );
-		$retval     = array_merge( $retval, $site_terms );
+
+		if ( ! is_wp_error( $site_terms ) ) {
+			$retval = array_merge( $retval, $site_terms );
+		}
 
 		if ( $switched ) {
 			restore_current_blog();
diff --git src/bp-core/classes/class-bp-user-query.php src/bp-core/classes/class-bp-user-query.php
index 68b4fbf56..0e36404f4 100644
--- src/bp-core/classes/class-bp-user-query.php
+++ src/bp-core/classes/class-bp-user-query.php
@@ -253,6 +253,10 @@ class BP_User_Query {
 			'limit'   => ''
 		);
 
+		if ( ! isset( $bp->members->table_name_last_activity ) || ! $bp->members->table_name_last_activity ) {
+			$bp->members->table_name_last_activity = bp_core_get_table_prefix() . 'bp_activity';
+		}
+
 		/* TYPE **************************************************************/
 
 		// Determines the sort order, which means it also determines where the