Hello, First, I'd like to thank you both for your answers! MrJinje, I tried your method but it didn't work. Here is what I did exactly: -Launched gpedit.msc, change password settings then Exit. -Copied the folder GroupPolicy from the system32 directory to myXpRoot\$OEM$\$$\system32 -Created a .iso with nLite -Virtualized with Sun Virtualbox, but nothing happened, even after a gpupdate /force I could create an user with a basic password. Also I found something about it here: http://www.hydre.org/drupal/node/14 (it's in French) Basically it explains that the key concerning the password complexity is located in HKLM\SAM\SAM\Domains\Account\F which is unaccesible without using psexec. To see it, you'll have to type in command line psexec -s -i -d c:\windows\regedit.exe. Open the F key: 00000000 02 00 01 00 00 00 00 00 - 86 13 ff ee 53 4f c9 01 ..........ÿîSOÉ. 00000010 2d 00 00 00 00 00 00 00 - 00 c0 53 7d fb ee fc ff -........ÀS}ûîüÿ 00000020 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 00 80 ................ 00000030 00 cc 1d cf fb ff ff ff - 00 cc 1d cf fb ff ff ff .Ì.Ïûÿÿÿ.Ì.Ïûÿÿÿ 00000040 00 00 00 00 00 00 00 00 - ec 03 00 00 00 00 00 00 ........ì....... 00000050 00 00 18 00 00 00 00 00 - 01 00 00 00 03 00 00 00 ................ 00000060 01 00 00 00 01 00 01 00 - 01 00 00 00 38 00 00 00 ............8... 00000070 8e e1 10 7b 7b 28 30 53 - c9 a0 a2 98 e8 92 50 14 .á.{{(0SÉ ¢.è.P. 00000080 86 10 6a 00 42 46 39 7c - 73 ef d8 ed 63 94 07 d7 ..j.BF9|sïØíc..× 00000090 b1 38 60 64 b5 68 26 ac - 72 42 60 a0 82 41 98 7b ±8`dµh&¬rB` .A.{ 000000a0 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 00 00 ................ 000000b0 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 00 00 ................ 000000c0 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 00 00 ................ 000000d0 00 00 00 00 00 00 00 00 - 00 00 00 00 00 00 00 00 ................ 000000e0 00 00 00 00 00 00 00 00 - 01 00 00 00 00 00 00 00 ................ The digit in red is the one that concerns the password complexity. If it's 0=>no pw complexity required, if 1=>pw complexity required. I tried to export/import the modified .reg file but it didn't work neither...