diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 62c9504c5dbf750ad5f7165d6261e3e7c6fed3d2..ecb011e99179399e62f646f3027951aff0163466 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -24,6 +24,7 @@
 set(test_cases
     test_connection
     test_transaction
+	#test_file_transmission TODO add once fixed
     test_ccaosdb
     )
 
diff --git a/test/test_file_transmission.cpp b/test/test_file_transmission.cpp
index 42911bc520191a0880b6d80d8d122134413a5201..eab5b785fcd15510b7aebce0d8a72bc78fb05fff 100644
--- a/test/test_file_transmission.cpp
+++ b/test/test_file_transmission.cpp
@@ -36,6 +36,12 @@ using caosdb::entity::v1alpha1::RegisterFileUploadResponse;
 using caosdb::entity::v1alpha1::RegistrationStatus;
 using caosdb::entity::v1alpha1::TransmissionStatus;
 
+
+// TODO(tf) this file is currently not used (see CMakeLists.txt)
+// Is it still necessary or is it obsolete due to test_transaction.cpp?
+// RegisterFileDownloadResponse is currently not defined by proto or the h
+// file.
+
 class test_file_transmission : public ::testing::Test {
 protected:
   void SetUp() override {}