Fatal error: Allowed memory size of 33554432 bytes exhausted in magento

This is because of the PHP Memory Limit.
Here is how to fix.
Goto your website root from FTP.
You will see a file called php.ini.sample
Rename it to php.ini
Edit that file and Copy/Paste this code at last,
   extension=pdo.so
   extension=pdo_mysql.so
  extension=pdo_sqlite.so