Content originally posted in LPCWare by sundarapandian on Tue Apr 08 16:48:25 MST 2014 Please try lpcopen package at http://www.lpcware.com/system/files/lpcopen_2_09_keil_iar_keil_mcb_4357_1.zip, If you are using keil open "applications\lpc18xx_43xx\keil_uvision_projects\keil_mcb_4357\keil_mcb_4357_lpcusblib_host_examples.uvmpw" and IAR workspace is under "applications\lpc18xx_43xx\iar_ewarm_projects".
If you want to use LPCXpresso, download the attached zip file unzip the contents into "applications/lpc_18xx_43xx" (use the package from the link above), now open LPCXpresso use the "Import Project(s) from xml description" from the "Quickstart Panel" and select "applications\lpc18xx_43xx\lpcxpresso_xml_projects\keil_mcb_4357\LPCUSBlib.xml". Click next and select "libchip, libboard and masstorage example" from it.