Cannot remove .old-php during package install

[dlancea]

I'm trying to install the PHP_Beautifier PEAR package using pyrus.phar and I get the following error message.

Warning: rename(C:\xampp\php,C:\xampp\.old-php): The process cannot access the file because it is being used by another process. (code: 32) in phar://C:/xampp/php/pyrus.phar/Pyrus-2.0.0a4/php/Pyrus/AtomicFileTransaction/Transaction/TwoStage.php on line 82

Call Stack:
    1.6045    1219984   1. {main}() C:\xampp\php\pyrus.phar:0
    1.6394    2195856   2. Pyrus\ScriptFrontend\Commands->run() C:\xampp\php\pyrus.phar:69
   15.6083    3808112   3. Pyrus\ScriptFrontend\Commands->install() phar://C:/xampp/php/pyrus.phar/Pyrus-2.0.0a4/php/Pyrus/ScriptFrontend/Commands.php:309
   16.0695    4828840   4. Pyrus\Installer::commit() phar://C:/xampp/php/pyrus.phar/Pyrus-2.0.0a4/php/Pyrus/ScriptFrontend/Commands.php:559
  113.4185    9393336   5. Pyrus\AtomicFileTransaction::commit() phar://C:/xampp/php/pyrus.phar/Pyrus-2.0.0a4/php/Pyrus/Installer.php:344
  113.4185    9393360   6. Pyrus\AtomicFileTransaction\Manager->commit() phar://C:/xampp/php/pyrus.phar/Pyrus-2.0.0a4/php/Pyrus/AtomicFileTransaction.php:90
  113.5336    9393440   7. Pyrus\AtomicFileTransaction\Transaction\TwoStage->commit() phar://C:/xampp/php/pyrus.phar/Pyrus-2.0.0a4/php/Pyrus/AtomicFileTransaction/Manager.php:165
  113.5338    9393472   8. rename() phar://C:/xampp/php/pyrus.phar/Pyrus-2.0.0a4/php/Pyrus/AtomicFileTransaction/Transaction/TwoStage.php:82

Pyrus\Installer\Exception: Installation failed
 Pyrus\AtomicFileTransaction\MultiException: ERROR: commit failed
  Pyrus\IOException: CRITICAL - unable to complete transaction, rename of actual to backup path failed
   Pyrus\AtomicFileTransaction\RuntimeException: Cannot rollback - not in a transaction

This is on Windows 7 using an XAMPP install of PHP 5.4.7, Pyrus version 2.0.0a4.