在新部署CakePHP项目或者从SVN中重新Update项目的时候，有时候会出现下面的警告：
Warning (512): D:xampphtdocsxxxxapp mpcache is not writable [COREcakelibscachefile.php, line 281] Warning (512): persistent is not writable [COREcakelibscachefile.php, line 281] Warning (512): models is not writable [COREcakelibscachefile.php, line 281] Warning (2): Cannot modify header information - headers already sent by (output started at D:xampphtdocsxxxxcakelibsdebugger.php:686) [APPapp_controller.php, line 52]
这是因为app下tmp文件丢失的原因，tmp文件夹中存放的是系统生成的临时文件，在导出系统的时候一般会忽略。解决的办法就新建tmp及其子文件夹，tmp的文件夹结构如下：
