diff --git a/Classes/PHPExcel/Reader/Excel2007.php b/Classes/PHPExcel/Reader/Excel2007.php
index bf387a0..1932df4 100644
--- a/Classes/PHPExcel/Reader/Excel2007.php
+++ b/Classes/PHPExcel/Reader/Excel2007.php
@@ -960,8 +960,9 @@ class PHPExcel_Reader_Excel2007 extends PHPExcel_Reader_Abstract implements PHPE
                                     }
 
                                     // Extract all cell references in $ref
-                                    foreach (PHPExcel_Cell::extractAllCellReferencesInRange($ref) as $reference) {
-                                        $docSheet->getStyle($reference)->setConditionalStyles($conditionalStyles);
+                                    $cellBlocks = explode(' ', str_replace('$', '', strtoupper($ref)));
+                                    foreach ($cellBlocks as $cellBlock) {
+                                        $docSheet->getStyle($cellBlock)->setConditionalStyles($conditionalStyles);
                                     }
                                 }
                             }
diff --git a/changelog.txt b/changelog.txt
index 2b7c4a7..ab75211 100644
--- a/changelog.txt
+++ b/changelog.txt
@@ -32,6 +32,7 @@ Planned for 1.8.2
 - Feature:  (MBaker)                            - Initial implementation of SUMIFS() function
 - Feature:  (MBaker)                            - Additional codepages
 - Feature:  (Tomino2112)      Work Item GH-808  - MemoryDrawing not working in HTML writer
+- General:  (rentalhost)      Work Item GH-575  - Excel 2007 Reader freezes because of conditional formatting
 
 
 2015-04-30 (v1.8.1):