diff --git a/src/mathed/InsetMathMacro.cpp b/src/mathed/InsetMathMacro.cpp
index 3a8ec4de0a..668562899d 100644
--- a/src/mathed/InsetMathMacro.cpp
+++ b/src/mathed/InsetMathMacro.cpp
@@ -800,11 +800,13 @@ bool InsetMathMacro::validName() const
 		return false;*/
 
 	// valid characters?
-	for (size_t i = 0; i<n.size(); ++i) {
-		if (!(n[i] >= 'a' && n[i] <= 'z')
-		    && !(n[i] >= 'A' && n[i] <= 'Z')
-		    && n[i] != '*')
-			return false;
+	if (n.size() > 1) {
+		for (size_t i = 0; i<n.size(); ++i) {
+			if (!(n[i] >= 'a' && n[i] <= 'z')
+			    && !(n[i] >= 'A' && n[i] <= 'Z')
+			    && n[i] != '*')
+				return false;
+		}
 	}
 
 	return true;
diff --git a/src/mathed/InsetMathMacroTemplate.cpp b/src/mathed/InsetMathMacroTemplate.cpp
index 8435d4819b..2dc2b98b03 100644
--- a/src/mathed/InsetMathMacroTemplate.cpp
+++ b/src/mathed/InsetMathMacroTemplate.cpp
@@ -1292,11 +1292,13 @@ bool InsetMathMacroTemplate::validName() const
 		return false;*/
 
 	// valid characters?
-	for (size_t i = 0; i < n.size(); ++i) {
-		if (!(n[i] >= 'a' && n[i] <= 'z')
-		    && !(n[i] >= 'A' && n[i] <= 'Z')
-		    && n[i] != '*')
-			return false;
+	if (n.size() > 1) {
+		for (size_t i = 0; i < n.size(); ++i) {
+			if (!(n[i] >= 'a' && n[i] <= 'z')
+			    && !(n[i] >= 'A' && n[i] <= 'Z')
+			    && n[i] != '*')
+				return false;
+		}
 	}
 
 	return true;