diff --git a/store/sqlstore/channel_store_categories.go b/store/sqlstore/channel_store_categories.go
index 94f0fea0a2..82d63779cb 100644
--- a/store/sqlstore/channel_store_categories.go
+++ b/store/sqlstore/channel_store_categories.go
@@ -396,6 +396,8 @@ func (s SqlChannelStore) completePopulatingCategoryChannelsT(db dbSelecter, cate
 			sq.Eq{"Channels.Type": []model.ChannelType{model.ChannelTypeOpen, model.ChannelTypePrivate}},
 			sq.Eq{"Channels.TeamId": category.TeamId},
 		}
+	} else {
+		return nil, fmt.Errorf("invalid category type: %q", category.Type)
 	}
 
 	// A subquery that is true if the channel does not have a SidebarChannel entry for the current user on the current team