IDLResource Failed!

[Hakurah]

Some of my players are having this problem.
This is the part of mlog.txt that shows this error up.
I've looked on Google but no one has ever given an answer to this error.

IDLResource Loading Failed!!
IDL resources : 0.002000
start InitInterface option
end of InitInterface option ok
quest combat list loding error
Failed: ZGameInterface OnCreate
Destroy interface begin
destroy client.
PeerInfoList Released
clear looks end.
Widget map clear end.
desctroy cursor system end.
clear IDL resource end.
Final interface end.
Destroy game interface done.
Crash ( 19:13:25 )
Build Jul 21 2008 11:25:55

dwTotalMemKB = 1038584 KB
dwAvailMemKB = 48432 KB
dwVirtualMemKB = 2097024 KB

[Exception]
Address : 00475824
ExpCode : c0000005
Flags : 00000000
#Param : 00000002
other : 00000000

[Context]
GS : 00000000 FS : 0000003b ES : 00000023 DS : 00000023
EDI: 00000000 ESI: 069d12e8 EBX: 069d14a4 EDX: 76e264f4
ECX: 0000000c EAX: 00000000 EBP: 0012e8d0 EIP: 00475824
CS : 0000001b Flg: 00210206 ESP: 0012e8c0 SS : 00000023

[Stack]
069d12e8 069d12e8 00000000 00000000 0012e8f4 004758fd 069d12e8 0697c3b0
00000000 069d12e8 0012e90c 00611f33 00000001 0012e918 004448a8 006abd00
0697c3b0 00000000 0697c3b0 0012eb14 006106aa 00000007 0012e924 00444a2b
0697c3b0 0012eb20 00499e4b 00000001 00000000 05a62550 ffffffff 00000001
000f4240 006abd00 000478d2 0697c3b0 00000024 00000001 00000000 00000000
00000070 ffffffff ffffffff 7557881f 755788c9 7556cccc 00000001 00000000
00000000 0012e940 0012e9a8 0012e9e8 755c62e3 67121434 fffffffe 7557888d
755770f4 656d6147 65746e49 63616672 00000065 00000001 c000000f 025eaf7c
755770ff 1257755c 025eaf68 00000281 00000000 0012e9e8 704d5079 00000000
0012e9c4 0012ed54 3df5c28f 3df5c28f 3eb33333 3e7ae147 6e756f53 00000064
0012ea18 75635123 00000f50 0000c03e 00000012 00000000 0012ea58 7563439e
75633ad3 12578d1e 006ad2b0 006ad2b0 ffffffff 76e263e0 0012ed54 00000000
00000000 3df5c28f 3f800000 7569319b 67265d9e fffffffe 75633ad3 75573560
000a0008 00000000 f0100416 0012eaac 755731eb 000a0008 00000000 f0100416
755731fd 12577608 006ad2b0 006ad2b0 ffffffff 0012ea84 00000281 0012eae0
755c62e3 6712aea4 fffffffe 755731fd 75573245 0012eae8 f0100416 75573255

clear looks end.
Widget map clear end.
desctroy cursor system end.

[MentaL]