diff --git a/provider/provider.go b/provider/provider.go
index bc9ccdb..d2a57f9 100644
--- a/provider/provider.go
+++ b/provider/provider.go
@@ -222,7 +222,10 @@ func (p ProviderConfig) Authenticate(t *OAuth2Token) error {
 	}
 
 	//TODO Drop privileges
-	exec.Command(c[0], c[1:]...).Start()
+	err = exec.Command(c[0], c[1:]...).Start()
+	if err != nil {
+		return err
+	}
 
 	go func() {
 		server.Serve(listener)