为何装WinCE时有的文件要做如下更新

安装2410开发板的WinCE.NET&nbsp;4.2装成功后，需要更新的文件如下：<br />1．&nbsp;&nbsp;&nbsp;&nbsp;备份WINCE420PUBLICCOMMONOAKLIBARMV4RETAIL目录下的文件<br />unimodem.def,unimodem.lib,unimodem.pdb,unimodem.res,从disk4中拷贝”更新文件Unimodem-lib”目录下的四个文件到<br />WINCE420PUBLICCOMMONOAKLIBARMV4RETAIL。<br />2．备份WINCE420PUBLICCOMMONOAKFILES目录下的common.reg,<br />,从disk4中拷贝disk4的”更新文件common-reg”目录下的common.reg文件到<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;WINCE420PUBLICCOMMONOAKFILES<br />&nbsp;&nbsp;&nbsp;&nbsp;3．备份WINCE420PRIVATEWINCEOSCOMMTAPI目录下的UNIMODEM,<br />,从disk4中拷贝”更新文件”目录下的UNIMODEM文件夹到<br />&nbsp;&nbsp;&nbsp;&nbsp;WINCE420PRIVATEWINCEOSCOMMTAPI<br />&nbsp;&nbsp;&nbsp;&nbsp;4．备份WINCE420PUBLICCOMMONOAKDRIVERSETHDBG目录下的<br />BOOTPART,从disk4中拷贝”更新文件”目录下的&nbsp;BOOTPART文件夹到<br />&nbsp;&nbsp;&nbsp;&nbsp;WINCE420PUBLICCOMMONOAKDRIVERSETHDBG<br />&nbsp;&nbsp;&nbsp;&nbsp;5．拷贝“SMDK2410\_for_PublicCESYSGEN”目录下的Makefile文件到“WINCE420PUBLICCOMMONCESYSGEN”目录下。<br />为何装WinCE时有的文件要做如下更新？？？<br />请高手指点迷津