Function at 0x403d10
Capabilities:
Check if file exists
Delete file
Get disk size

Disassembly:
sub esp, 0x430
mov eax, dword [0x4b0650]
xor eax, esp
mov dword [esp + 0x42c], eax
push ebx
push esi
mov esi, dword [esp + 0x43c]
xor ebx, ebx
cmp esi, ebx
push edi
mov edi, ecx
je 0x403f62
mov eax, esi
lea edx, [eax + 2]
nop
mov cx, word [eax]
add eax, 2
cmp cx, bx
jne 0x403d40
sub eax, edx
sar eax, 1
je 0x403f62
push ebp
push str.MultiBlockDownloader::ChangeTarget__
call fcn.00401030
push 0x206
lea eax, [esp + 0x36]
push ebx
mov ebp, 0x80004005
push eax
mov dword [esp + 0x20], ebp
mov word [esp + 0x3c], bx
call fcn.00477c40
lea edx, [esp + 0x3c]
add esp, 0x10
mov eax, esi
sub edx, esi
lea esp, [esp]
movzx ecx, word [eax]
mov word [edx + eax], cx
add eax, 2
cmp cx, bx
jne 0x403d90
lea ecx, [esp + 0x2c]
push ecx
call dword [sym.imp.SHLWAPI.dll_PathRemoveFileSpecW]
lea edx, [esp + 0x1c]
push edx
lea eax, [esp + 0x28]
push eax
lea ecx, [esp + 0x1c]
push ecx
lea edx, [esp + 0x38]
push edx
call dword [sym.imp.KERNEL32.dll_GetDiskFreeSpaceExW]
test eax, eax
jne 0x403e45
lea eax, [esp + 0x10]
push str.GetDiskFreeSpaceEx
push eax
call fcn.004012f0
add esp, 8
call dword [sym.imp.KERNEL32.dll_GetLastError]
push 0x206
lea ecx, [esp + 0x23a]
push ebx
push ecx
mov esi, eax
mov word [esp + 0x240], bx
call fcn.00477c40
push esi
push str._ERROR_GetDiskFreeSpaceEx_failed___dwErrorCode___.8X
lea edx, [esp + 0x248]
push 0x104
push edx
call fcn.00477bdc
lea eax, [esp + 0x250]
push eax
call fcn.00401030
add esp, 0x20
mov eax, 0x80070005
pop ebp
mov ecx, dword [esp + 0x438]
pop edi
pop esi
pop ebx
xor ecx, esp
call fcn.00477bf8
add esp, 0x430
ret 4
mov ecx, dword [edi + 0x1f8]
sub ecx, dword [edi + 0x208]
mov eax, dword [edi + 0x1fc]
sbb eax, dword [edi + 0x20c]
mov edx, dword [esp + 0x18]
cmp edx, eax
ja 0x403e83
jb 0x403e6f
mov eax, dword [esp + 0x14]
cmp eax, ecx
jae 0x403e83
push str._ERROR__E_MBD_NO_DISK_SPACE_
call fcn.00401030
add esp, 4
mov eax, 0x80700007
jmp 0x403e2a
lea ecx, [esp + 0x2c]
push ecx
call dword [sym.imp.SHLWAPI.dll_PathFileExistsW]
test eax, eax
jne 0x403ea0
lea edx, [esp + 0x2c]
push edx
push ebx
call dword [sym.imp.SHELL32.dll_SHCreateDirectory]
jmp 0x403e2a
push 0x493e30
push esi
call fcn.00477f07
add esp, 8
cmp eax, ebx
jne 0x403ec4
push str._ERROR___wfopen_failed__E_ACCESSDENIED
call fcn.00401030
add esp, 4
jmp 0x403e25
push eax
call fcn.00477fdc
add esp, 4
push esi
call dword [sym.imp.KERNEL32.dll_DeleteFileW]
mov ecx, edi
sub ecx, esi
mov eax, esi
lea edx, [ecx + 0x22c]
movzx ecx, word [eax]
mov word [edx + eax], cx
add eax, 2
cmp cx, bx
jne 0x403ee0
lea ebx, [edi + 0x434]
mov edx, ebx
mov eax, esi
sub edx, esi
jmp 0x403f00
movzx ecx, word [eax]
mov word [edx + eax], cx
add eax, 2
test cx, cx
jne 0x403f00
push ebx
call dword [sym.imp.SHLWAPI.dll_PathRemoveExtensionW]
xor esi, esi
add edi, 0x21c
mov edi, edi
mov ecx, dword [edi + 4]
test ecx, ecx
je 0x403f5b
mov eax, dword [edi + 8]
sub eax, ecx
sar eax, 2
cmp esi, eax
jae 0x403f5b
push esi
mov ecx, edi
call fcn.00401a00
mov ecx, dword [eax]
push ebx
call fcn.00401c80
push esi
mov ecx, edi
call fcn.00401a00
mov ecx, dword [eax]
push 0x10
call fcn.00403960
mov ebp, eax
add esi, 1
jmp 0x403f20
mov eax, ebp
jmp 0x403e2a
mov eax, 0x80070057
jmp 0x403e2b