diff --git a/ndn-cpp/c/util/DynamicUCharArray.c b/ndn-cpp/c/util/DynamicUCharArray.c
index 30b0814..eb28072 100644
--- a/ndn-cpp/c/util/DynamicUCharArray.c
+++ b/ndn-cpp/c/util/DynamicUCharArray.c
@@ -5,10 +5,10 @@
 
 #include "DynamicUCharArray.h"
 
-char *ndn_DynamicUCharArray_reallocArray(struct ndn_DynamicUCharArray *self, unsigned int length)
+ndn_Error ndn_DynamicUCharArray_reallocArray(struct ndn_DynamicUCharArray *self, unsigned int length)
 {
   if (!self->realloc)
-    return "ndn_DynamicUCharArray_reallocArray: realloc function pointer not supplied";
+    return NDN_ERROR_DynamicUCharArray_realloc_function_pointer_not_supplied;
   
   // See if double is enough.
   unsigned int newLength = self->length * 2;
@@ -18,7 +18,7 @@
     
   unsigned char *newArray = (*self->realloc)(self->array, newLength);
   if (!newArray)
-    return "ndn_DynamicUCharArray_reallocArray: realloc failed";
+    return NDN_ERROR_DynamicUCharArray_realloc_failed;
   
   self->array = newArray;
   self->length = newLength;
diff --git a/ndn-cpp/c/util/DynamicUCharArray.h b/ndn-cpp/c/util/DynamicUCharArray.h
index 6647680..d8d0d23 100644
--- a/ndn-cpp/c/util/DynamicUCharArray.h
+++ b/ndn-cpp/c/util/DynamicUCharArray.h
@@ -6,6 +6,7 @@
 #ifndef NDN_DYNAMICUCHARARRAY_H
 #define	NDN_DYNAMICUCHARARRAY_H
 
+#include "../errors.h"
 #include "ndn_memory.h"
 
 #ifdef	__cplusplus
@@ -42,9 +43,9 @@
  * If not null, call self->realloc to reallocate self->array, and update self->length (which may be greater than length).
  * @param self pointer to the ndn_DynamicUCharArray struct
  * @param length the needed minimum size for self->length
- * @return 0 for success, else an error string if can't reallocate the array
+ * @return 0 for success, else an error code if can't reallocate the array
  */
-char *ndn_DynamicUCharArray_reallocArray(struct ndn_DynamicUCharArray *self, unsigned int length);
+ndn_Error ndn_DynamicUCharArray_reallocArray(struct ndn_DynamicUCharArray *self, unsigned int length);
 
 /**
  * Ensure that self->length is greater than or equal to length.  If it is, just return 0 for success.
@@ -52,12 +53,12 @@
  * If not null, call self->realloc to reallocate self->array, and update self->length (which may be greater than length).
  * @param self pointer to the ndn_DynamicUCharArray struct
  * @param length the needed minimum size for self->length
- * @return 0 for success, else an error string if need to reallocate the array but can't
+ * @return 0 for success, else an error code if need to reallocate the array but can't
  */
-static inline char *ndn_DynamicUCharArray_ensureLength(struct ndn_DynamicUCharArray *self, unsigned int length) 
+static inline ndn_Error ndn_DynamicUCharArray_ensureLength(struct ndn_DynamicUCharArray *self, unsigned int length) 
 {
   if (self->length >= length)
-    return 0;
+    return (ndn_Error)0;
 
   return ndn_DynamicUCharArray_reallocArray(self, length);
 }
@@ -68,12 +69,12 @@
  * @param value the buffer to copy from
  * @param valueLength the length of the value buffer
  * @param offset the offset in self->array to copy to
- * @return 0 for success, else an error string if need to reallocate the array but can't
+ * @return 0 for success, else an error code if need to reallocate the array but can't
  */
-static inline char *ndn_DynamicUCharArray_set
+static inline ndn_Error ndn_DynamicUCharArray_set
   (struct ndn_DynamicUCharArray *self, unsigned char *value, unsigned int valueLength, unsigned int offset) 
 {
-  char *error;
+  ndn_Error error;
   if (error = ndn_DynamicUCharArray_ensureLength(self, valueLength + offset))
     return error;
   ndn_memcpy(self->array + offset, value, valueLength);