diff -rU3 zathura-0.2.3/document.c zathura-0.2.3-patched/document.c
--- zathura-0.2.3/document.c	2013-05-12 23:28:52.000000000 +0200
+++ zathura-0.2.3-patched/document.c	2013-05-28 21:24:19.585439351 +0200
@@ -110,6 +110,7 @@
 
   if (plugin == NULL) {
     girara_error("unknown file type\n");
+    error = ZATHURA_ERROR_UNKNOWN;
     goto error_free;
   }
 
diff -rU3 zathura-0.2.3/zathura.c zathura-0.2.3-patched/zathura.c
--- zathura-0.2.3/zathura.c	2013-05-12 23:28:52.000000000 +0200
+++ zathura-0.2.3-patched/zathura.c	2013-05-28 21:24:25.955414704 +0200
@@ -578,6 +578,9 @@
       }
       goto error_out;
     }
+    if (error == ZATHURA_ERROR_OK ) {
+      girara_notify(zathura->ui.session, GIRARA_ERROR, _("Unsupported file type. Please install the necessary plugin."));
+    }
     goto error_out;
   }