到網上下載一個php的mcrypt模塊安裝包，只需要libmcrypt.dll文件即可（一般官網上下載的，php目錄下已經有的）
1.將libmcrypt.dll複製到system32目錄或php安裝目錄下的ext目錄下
2.將libmcrypt.dll複製到apache安裝目錄的bin目錄下
3.到windows目錄下找到php.ini文件，打開它 ，找到; Directory in which the loadable extensions (modules) reside. extension_dir = "./" 如：extension_dir = "D:\php5\ext" ，這兩行，要使extension_dir指向的目錄下能找到libmcrypt.dll，或系統path下有libmcrypt.dll
4.找到;Windows Extensions 項下面的;extension=php_mcrypt.dll這一行和;extension=php_iconv.dll
