well, opening the files told me that HKCR=HIVECLS.INF, HKCU=HIVEDEF.INF and HKLM=HIVESFT.INF and HIVESYS.INF. Untill now this is what i've figured out as the format, HKLM,"SOFTWARE\Microsoft\Windows\CurrentVersion\Applets\Tour","RunCount",0x00010003,0 HKLM=Hkey Local Machine between " and " the folder path "RunCount" value name 0x00010003, meant to signify the type of data i.e dword, sz etc next value is the data value, also i think the values are in hex, so Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters] GlobalMaxTcpWindowSize="256960" TcpWindowSize="256960" Tcp1323Opts="1" DefaultTTL="64" EnablePMTUDiscovery="1" EnablePMTUBHDetect="0" SackOpts="1" TcpMaxDupAcks="2" MTU="1500" would be [Addreg] HKLM,"SYSTEM\CurrentControlSet\Services\Tcpip\Parameters","GlobalMaxTcpWindowSize",0x00010003,0x3EBC0 HKLM,"SYSTEM\CurrentControlSet\Services\Tcpip\Parameters","TcpWindowSize",0x00010003,0x3EBC0 HKLM,"SYSTEM\CurrentControlSet\Services\Tcpip\Parameters","Tcp1323Opt",0x00010003,1 HKLM,"SYSTEM\CurrentControlSet\Services\Tcpip\Parameters","DefaultTTL",0x00010003,64 HKLM,"SYSTEM\CurrentControlSet\Services\Tcpip\Parameters","EnablePMTUDiscovery",0x00010003,1 HKLM,"SYSTEM\CurrentControlSet\Services\Tcpip\Parameters","EnablePMTUBHDetect",0x00010003,0 HKLM,"SYSTEM\CurrentControlSet\Services\Tcpip\Parameters","SackOpts",0x00010003,1 HKLM,"SYSTEM\CurrentControlSet\Services\Tcpip\Parameters","TcpMaxDupAcks",0x00010003,2 HKLM,"SYSTEM\CurrentControlSet\Services\Tcpip\Parameters","MTU",0x00010003,0x5DC is this right, i needed a way to add common registry settings for the entire system one time only, if i'm successfull i'll post the codes.