diff --git a/src/dump_atom.cpp b/src/dump_atom.cpp
index 293ade6229..dfacf8f2da 100644
--- a/src/dump_atom.cpp
+++ b/src/dump_atom.cpp
@@ -166,11 +166,12 @@ int DumpAtom::modify_param(int narg, char **arg)
   }
 
   if (strcmp(arg[0],"triclinic/general") == 0) {
-    triclinic_general = 1;
+    if (narg < 2) error->all(FLERR,"Illegal dump_modify command");
+    triclinic_general = utils::logical(FLERR,arg[1],false,lmp);
     if (triclinic_general && !domain->triclinic_general)
       error->all(FLERR,"Dump_modify triclinic/general cannot be used "
                  "if simulation box is not general triclinic");
-    return 1;
+    return 2;
   }
 
   return 0;
diff --git a/src/dump_custom.cpp b/src/dump_custom.cpp
index fb07efd561..431dd62fb7 100644
--- a/src/dump_custom.cpp
+++ b/src/dump_custom.cpp
@@ -1766,7 +1766,8 @@ int DumpCustom::modify_param(int narg, char **arg)
     if (narg < 2) error->all(FLERR,"Illegal dump_modify command");
     triclinic_general = utils::logical(FLERR,arg[1],false,lmp);
     if (triclinic_general && !domain->triclinic_general)
-      error->all(FLERR,"Dump_modify triclinic/general invalid b/c simulation box is not");
+      error->all(FLERR,"Dump_modify triclinic/general cannot be used "
+                 "if simulation box is not general triclinic");
     return 2;
   }