Hello again, just tried it again with another pc ... copied the complete i386 directory from an original xp installation cd (sp2) to my harddisk and started slipstreaming with method 1 after step 1 copied the complete content of UWXPCD_ROOT to the "root" of the xp directory on my hdd (giving c:\test\i386, c:\test\DPfiles and c:\test\M1) after that started the run_me.cmd in the root of the "cd" c:\test\run_me.cmd few minutes later i have the directories c:\test\$oem$ and c:\test\i386 in i386 i have a new dosnet.inf containing the entries [Files] ... d1,portcls.sys [ForceCopyDriverCabFiles] portcls.sys and a new txtsetup.sif containing [sourceDisksFiles] ... portcls.sys = 100,,,,,,,4,0,3 the other "new" files in i386 are the repacked mass storage drivers and the files from the patch kb888111: hdaprop.dl_ hdashcut.ex_ hdaudbus.in_ hdaudbus.sy_ hdaudio.in_ hdaudio.sy_ hdaudres.dl_ but no portcls.sy_ or portcls.sys file in the directory now i copy the whole directories to a (new) network share and start installation and receive the error "portcls.sys missing" ok ... am i doing wrong? maybe the xp setup from a network share is a little more sensitive than the xp setup from a cd if a file is missing ?