Fix #3771
diff --git a/system/libraries/Form_validation.php b/system/libraries/Form_validation.php
index 522eba7..bb872c7 100644
--- a/system/libraries/Form_validation.php
+++ b/system/libraries/Form_validation.php
@@ -870,17 +870,11 @@
 	 */
 	protected function _translate_fieldname($fieldname)
 	{
-		// Do we need to translate the field name?
-		// We look for the prefix lang: to determine this
-		if (sscanf($fieldname, 'lang:%s', $line) === 1)
+		// Do we need to translate the field name? We look for the prefix 'lang:' to determine this
+		// If we find one, but there's no translation for the string - just return it
+		if (sscanf($fieldname, 'lang:%s', $line) === 1 && FALSE === ($fieldname = $this->CI->lang->line($line, FALSE)))
 		{
-			// Were we able to translate the field name?  If not we use $line
-			if (FALSE === ($fieldname = $this->CI->lang->line('form_validation_'.$line))
-				// DEPRECATED support for non-prefixed keys
-				&& FALSE === ($fieldname = $this->CI->lang->line($line, FALSE)))
-			{
-				return $line;
-			}
+			return $line;
 		}
 
 		return $fieldname;
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index 596cd0f..5454638 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -18,6 +18,7 @@
 -  Fixed a bug (#3744) - Redis :doc:`Caching <libraries/caching>` driver didn't handle authentication failures properly.
 -  Fixed a bug (#3761) - :doc:`URL Helper <helpers/url_helper>` function :php:func:`anchor()` didn't work with array inputs.
 -  Fixed a bug (#3773) - ``db_select()`` didn't work for MySQL with the PDO :doc:`Database <database/index>` driver.
+-  Fixed a bug (#3771) - :doc:`Form Validation Library <libraries/form_validation>` was looking for a 'form_validation_' prefix when trying to translate field name labels.
 
 Version 3.0.0
 =============