diff --git a/plugin.go b/plugin.go
index 98f62b4..d857be9 100644
--- a/plugin.go
+++ b/plugin.go
@@ -70,9 +70,15 @@ func trimPath(keys []string) []string {
 func (p Plugin) Exec() error {
 
 	if len(p.Config.Host) == 0 || len(p.Config.Username) == 0 || (len(p.Config.Password) == 0 && len(p.Config.Key) == 0) {
-		log.Println("missing ssh config")
+		log.Println("missing ssh config (Host, Username, Password or Key)")
 
-		return errors.New("missing ssh config")
+		return errors.New("missing ssh config (Host, Username, Password or Key)")
+	}
+
+	if len(p.Config.Source) == 0 {
+		log.Println("missing source file list config")
+
+		return errors.New("missing source file list config")
 	}
 
 	files := trimPath(p.Config.Source)
diff --git a/plugin_test.go b/plugin_test.go
index 46fe72d..bc55c18 100644
--- a/plugin_test.go
+++ b/plugin_test.go
@@ -27,6 +27,21 @@ func TestMissingSSHConfig(t *testing.T) {
 	assert.NotNil(t, err)
 }
 
+func TestMissingSourceConfig(t *testing.T) {
+	plugin := Plugin{
+		Config: Config{
+			Host:     "example.com",
+			Username: "ubuntu",
+			Port:     "443",
+			Password: "1234",
+		},
+	}
+
+	err := plugin.Exec()
+
+	assert.NotNil(t, err)
+}
+
 func TestTrimElement(t *testing.T) {
 	var input, result []string