diff --git a/commands.go b/commands.go
index f0b6b00..de50d20 100644
--- a/commands.go
+++ b/commands.go
@@ -243,6 +243,10 @@ func (v *GenerateAndStoreCommand) validateFlags() error {
 	if v.CommonName == "" && len(v.SANDNS) == 0 {
 		return errors.New("you must have a common name or san-dns")
 	}
+	re := regexp.MustCompile(`[^\w_\-\/]`)
+	if re.MatchString(v.Name) {
+		return errors.New("CredHub name can only contain alphanumeric characters plus forward slash, underscore and dash")
+	}
 	return nil
 }
 
diff --git a/cv.go b/cv.go
index 042579e..c436fcc 100644
--- a/cv.go
+++ b/cv.go
@@ -250,12 +250,12 @@ func (c CertCompareData) String() string {
 	if c.Left != nil {
 		out += fmt.Sprintf(" Left:%+v ", *c.Left)
 	} else {
-		out += fmt.Sprintf(" Left: nil ")
+		out += " Left: nil "
 	}
 	if c.Right != nil {
 		out += fmt.Sprintf(" Right:%+v ", *c.Right)
 	} else {
-		out += fmt.Sprintf(" Right: nil ")
+		out += " Right: nil "
 	}
 	return out
 }