[help] Shit Xml Files

[kalo93]

I try to edit zitem blah blah blah but i try to log in and it says Cannot Access Server

heres my procedure:

i unpack system.mrs, edit zitem, put zitem into matchserver, then pack again and replace system.mrs with my current one, i run matchserver, try to log in but doesnt work.
this is my error in match server:

Invalid ZItemChecksum(13317901) , UserID(kalo93)

[MentaL]

[RepublicOfAstra]

SEARCH. This has been answered at least 50 times.