diff --git a/bintree.o b/bintree.o
index 48f3a9c..49eaac0 100644
Binary files a/bintree.o and b/bintree.o differ
diff --git a/bintreeTests.c b/bintreeTests.c
index c187aaf..495a8fb 100644
--- a/bintreeTests.c
+++ b/bintreeTests.c
@@ -3,6 +3,7 @@
 #include <stdlib.h>
 #include "unity.h"
 #include "bintree.h"
+#include "stack.h"
 
 #define MAX_TEST_NAME_LEN 10
 
@@ -89,7 +90,42 @@ void test_addToTreeExpandsTreeCorrectly(void)
 //      needs Stack!!!
 void test_nextTreeDataReturnsNextDataCorrectly(void)
 {
+    TreeNode    *testRoot       = NULL;
+    int         score1          = 12;
+    int         score2          = 6;
+    int         score3          = 18;
+    int         score4          = 3;
+    int         score5          = 9;
+    int         score6          = 15;
+    int         score7          = 21;
 
+
+    // Prepare a Tree
+    testRoot = addToTree(testRoot, &score1, sizeof(int), compareIntEntries, NULL);
+    testRoot = addToTree(testRoot, &score2, sizeof(int), compareIntEntries, NULL);
+    testRoot = addToTree(testRoot, &score3, sizeof(int), compareIntEntries, NULL);
+    testRoot = addToTree(testRoot, &score4, sizeof(int), compareIntEntries, NULL);
+    testRoot = addToTree(testRoot, &score5, sizeof(int), compareIntEntries, NULL);
+    testRoot = addToTree(testRoot, &score6, sizeof(int), compareIntEntries, NULL);
+    testRoot = addToTree(testRoot, &score7, sizeof(int), compareIntEntries, NULL);
+
+
+    // Create Stack
+    StackNode   *entry  = nextTreeData(testRoot);
+
+    // check if nextTreeData returns Data correctly
+    TEST_ASSERT_NOT_NULL(entry);
+
+    TEST_ASSERT_EQUAL(score7, *(int *)nextTreeData(NULL));
+    TEST_ASSERT_EQUAL(score3, *(int *)nextTreeData(NULL));
+    TEST_ASSERT_EQUAL(score6, *(int *)nextTreeData(NULL));
+    TEST_ASSERT_EQUAL(score1, *(int *)nextTreeData(NULL));
+    TEST_ASSERT_EQUAL(score5, *(int *)nextTreeData(NULL));
+    TEST_ASSERT_EQUAL(score2, *(int *)nextTreeData(NULL));
+    TEST_ASSERT_EQUAL(score4, *(int *)nextTreeData(NULL));
+
+    clearStack(entry);
+    clearTree(testRoot);
 }
 
 
diff --git a/runbintreeTests.exe b/runbintreeTests.exe
deleted file mode 100644
index 6e09e24..0000000
Binary files a/runbintreeTests.exe and /dev/null differ