diff --git a/src/MyFirstUDRKit.cpp b/src/MyFirstUDRKit.cpp
index 7fb12d9..089e23c 100644
--- a/src/MyFirstUDRKit.cpp
+++ b/src/MyFirstUDRKit.cpp
@@ -181,11 +181,12 @@ FB_UDR_MESSAGE(OutMessage,
 
 FB_UDR_EXECUTE_FUNCTION
 {
-// 	// Test Input
-// 	if (!s || !b || !b->blob_handle) {
-// 		return NULL;
-// 	}
-// 	// open for write & as a binary...
+	// Test Input
+	if (in->afilenameNull || in->ablobcallbackNull /* || in->ablobcallback.blob_handle == NULL */ ) {
+		out->resultNull = FB_TRUE;
+		out->result = 0;
+	}
+	// open for write & as a binary...
 // 	FILE* file_ = fopen(s, "wb");
 // 	if (file_ == NULL) {
 // 		ISC_INT64* res = MALLOC(sizeof(ISC_INT64));