Function at 0x4039a0
Capabilities:
Accept command line arguments
Check os version
Copy file
Delete file
Get common file path
Get file attributes
Get file system object information
Set current directory
Set environment variable
Shutdown system
Terminate process

Disassembly:
sub esp, 0x3f0
mov eax, dword [0x40b0cc]
xor eax, esp
mov dword [esp + 0x3ec], eax
push ebx
push ebp
push esi
push edi
call fcn.004081f0
xor edi, edi
mov ebx, str.Error_writing_temporary_file._Make_sure_your_temp_folder_is_valid.
push 0x8001
mov dword [esp + 0x14], edi
mov ebp, edi
call dword [sym.imp.KERNEL32.dll_SetErrorMode]
lea eax, [esp + 0x2c]
mov dword [esp + 0x40], edi
xorps xmm0, xmm0
mov dword [esp + 0x2c], 0x11c
push eax
movlpd qword [esp + 0x144], xmm0
call dword [sym.imp.KERNEL32.dll_GetVersionExW]
push 0x53
pop esi
test eax, eax
jne 0x403a37
lea eax, [esp + 0x2c]
mov dword [esp + 0x2c], 0x114
push eax
call dword [sym.imp.KERNEL32.dll_GetVersionExW]
mov dl, 4
mov byte [esp + 0x146], dl
cmp word [esp + 0x40], si
jne 0x403a33
mov eax, dword [esp + 0x5a]
add eax, 0xffffffd0
mov word [esp + 0x140], ax
jmp 0x403a3e
xor eax, eax
jmp 0x403a29
mov dl, byte [esp + 0x146]
cmp dword [esp + 0x30], 0xa
jae 0x403a50
movzx eax, word [esp + 0x38]
mov dword [esp + 0x38], eax
jmp 0x403a54
mov eax, dword [esp + 0x38]
mov dword [0x46d158], eax
movzx eax, byte [esp + 0x30]
shl ax, 8
movzx ecx, ax
movzx eax, byte [esp + 0x34]
or ecx, eax
movzx eax, byte [esp + 0x140]
shl ax, 8
shl ecx, 0x10
movzx eax, ax
or ecx, eax
movzx eax, dl
or ecx, eax
mov eax, 0x600
mov dword [0x46d15c], ecx
sar ecx, 0x10
cmp cx, ax
je 0x403ab3
push edi
call fcn.00406dcf
mov esi, eax
test esi, esi
je 0x403ab3
push 0xc00
mov ecx, esi
call dword [0x4092c8]
call esi
mov esi, str.UXTHEME
push esi
call fcn.0040661c
push esi
call dword [sym.imp.KERNEL32.dll_lstrlenA]
inc esi
add esi, eax
cmp byte [esi], 0
jne 0x403ab8
push 0xc
call fcn.00406dcf
push 0xa
call fcn.00406dcf
push 8
mov dword [0x465050], eax
call fcn.00406dcf
mov esi, eax
test esi, esi
je 0x403b04
push 0x1e
mov ecx, esi
call dword [0x4092c8]
call esi
test eax, eax
je 0x403b04
or byte [0x46d15c], 0x80
call dword [sym.imp.COMCTL32.dll_InitCommonControls]
push edi
call dword [sym.imp.ole32.dll_OleInitialize]
push edi
push 0x2b4
mov dword [0x46d0c0], eax
lea eax, [esp + 0x150]
push eax
push edi
push 0x40963c
call dword [sym.imp.SHELL32.dll_SHGetFileInfoW]
push str.NSIS_Error
push 0x465060
call fcn.0040701f
call dword [sym.imp.KERNEL32.dll_GetCommandLineW]
push eax
mov esi, 0x4be000
push esi
call fcn.0040701f
movzx ecx, word [0x4be000]
push 0x22
pop edi
push 0x20
pop edx
cmp cx, di
mov dword [0x465054], 0x400000
mov eax, edi
mov dword [esp + 0x14], edi
cmovne eax, edx
mov edx, 0x4be002
movzx eax, ax
push eax
mov eax, esi
cmove eax, edx
push eax
call fcn.00406ab7
push eax
call dword [sym.imp.USER32.dll_CharNextW]
mov ecx, eax
mov edi, ecx
mov dword [esp + 0x18], edi
movzx eax, word [ecx]
test ax, ax
je 0x403c7f
mov esi, eax
push 0x20
pop edx
movzx eax, si
cmp si, dx
jne 0x403bbb
add ecx, 2
movzx eax, word [ecx]
cmp ax, dx
je 0x403bb0
mov edi, edx
movzx esi, ax
movzx edx, ax
cmp ax, word [esp + 0x14]
jne 0x403bd3
movzx edx, word [ecx + 2]
push 0x22
pop eax
mov edi, eax
cmp si, word [esp + 0x14]
lea eax, [ecx + 2]
cmovne eax, ecx
cmp dx, 0x2f
jne 0x403c3d
push 0x53
add eax, 2
pop ecx
push 0x20
pop edx
cmp word [eax], cx
jne 0x403c0a
movzx ecx, word [eax + 2]
cmp cx, dx
je 0x403c00
test cx, cx
jne 0x403c0a
mov dword [0x46d140], 1
cmp dword [eax], 0x43004e
jne 0x403c2c
cmp dword [eax + 4], 0x430052
jne 0x403c2c
movzx ecx, word [eax + 8]
cmp cx, dx
je 0x403c29
test cx, cx
jne 0x403c2c
or ebp, 4
cmp dword [eax - 4], 0x2f0020
jne 0x403c3d
cmp dword [eax], 0x3d0044
je 0x403c67
push edi
push eax
call fcn.00406ab7
mov ecx, eax
push 0x22
pop esi
movzx eax, word [ecx]
mov edx, eax
cmp ax, si
jne 0x403c59
add ecx, 2
movzx edx, word [ecx]
movzx esi, dx
test dx, dx
jne 0x403ba5
jmp 0x403c7b
xor ecx, ecx
mov word [eax - 4], cx
add eax, 4
push eax
push 0x4c2000
call fcn.0040701f
mov edi, dword [esp + 0x18]
mov esi, 0x4d2000
push esi
push 0x2000
call dword [sym.imp.KERNEL32.dll_GetTempPathW]
call fcn.00403fc7
test eax, eax
jne 0x403cf5
push 0x1ffb
push esi
call dword [sym.imp.KERNEL32.dll_GetWindowsDirectoryW]
push str.Temp
push esi
call sub.KERNEL32.dll_lstrcatW
call fcn.00403fc7
test eax, eax
jne 0x403cf5
push esi
push 0x1ffc
call dword [sym.imp.KERNEL32.dll_GetTempPathW]
push 0x409664
push esi
call sub.KERNEL32.dll_lstrcatW
push esi
push str.TEMP
call dword [sym.imp.KERNEL32.dll_SetEnvironmentVariableW]
push esi
push 0x409678
call dword [sym.imp.KERNEL32.dll_SetEnvironmentVariableW]
call fcn.00403fc7
test eax, eax
je 0x403ed6
push 0x4ce000
call dword [sym.imp.KERNEL32.dll_DeleteFileW]
push ebp
call fcn.004035e6
mov ebx, eax
test ebx, ebx
jne 0x403ed6
cmp dword [0x46d064], eax
je 0x403d7d
xor ebp, ebp
push ebp
push 0x4be000
call fcn.00406ab7
mov esi, eax
mov eax, 0x4be000
jmp 0x403d42
cmp dword [esi], 0x5f0020
jne 0x403d3f
cmp dword [esi + 4], 0x3d003f
je 0x403d46
sub esi, 2
cmp esi, eax
jae 0x403d2e
mov ebx, str.Error_launching_installer
cmp esi, eax
jb 0x403d90
xor eax, eax
mov word [esi], ax
add esi, 8
push esi
call fcn.00406af9
test eax, eax
je 0x403eda
push esi
push 0x4c2000
call fcn.0040701f
push esi
push 0x4c6000
call fcn.0040701f
mov ebx, ebp
or dword [0x46d14c], 0xffffffff
call fcn.00405e5e
mov ebp, eax
jmp 0x403eda
call fcn.004069b0
push 0x4d2000
mov dword [esp + 0x1c], eax
call sub.KERNEL32.dll_lstrlenW
push edi
push section..ndata
mov esi, eax
call fcn.0040701f
cmp word [0x4c2000], bp
jne 0x403dc8
push 0x4ca000
push 0x4c2000
call fcn.0040701f
xor edi, edi
lea eax, [esi*2 + 0x4d2000]
inc edi
mov dword [esp + 0x14], eax
mov esi, ebp
movzx ebp, di
push ebp
push str.nsu_X.tmp
push eax
call dword [sym.imp.USER32.dll_wsprintfW]
mov eax, dword [0x46d070]
add esp, 0xc
push dword [eax + 0x120]
push 0x482000
call fcn.004062f1
cmp dword [esp + 0x18], 0
push 0x4d2000
je 0x403e13
call fcn.00406296
jmp 0x403e18
call fcn.00406276
test eax, eax
je 0x403e65
push 0x482000
call dword [sym.imp.KERNEL32.dll_GetFileAttributesW]
test eax, 0x400
jne 0x403efe
push 0x482000
call dword [sym.imp.KERNEL32.dll_DeleteFileW]
test eax, eax
je 0x403efe
push 1
push 0x4d2000
call fcn.00406bda
mov eax, esi
inc esi
test eax, eax
jne 0x403efe
mov eax, dword [esp + 0x14]
jmp 0x403ddb
push 0x4d2000
call dword [sym.imp.KERNEL32.dll_SetCurrentDirectoryW]
push 0
push 0x4d2000
call fcn.004066d2
push 1
push 0x482000
push 0x4da000
call dword [sym.imp.KERNEL32.dll_CopyFileW]
test eax, eax
je 0x403ed6
push 0
push 0x482000
call fcn.004066d2
mov eax, dword [0x46d070]
push dword [eax + 0x124]
push 0x486000
call fcn.004062f1
push 0x486000
call fcn.00406b97
test eax, eax
jne 0x403f11
mov eax, esi
inc esi
test eax, eax
jne 0x403ed6
push 0x482000
call fcn.00406a90
test eax, eax
je 0x403e5c
mov ebp, dword [esp + 0x10]
xor edi, edi
call fcn.00403957
call dword [sym.imp.ole32.dll_OleUninitialize]
test ebx, ebx
je 0x403f20
push 0x200010
push ebx
call fcn.00406fad
push 2
call dword [sym.imp.KERNEL32.dll_ExitProcess]
mov eax, dword [esp + 0x14]
inc edi
push 0
pop ebp
test di, di
jne 0x403dd6
jmp 0x403ed6
push eax
call dword [sym.imp.KERNEL32.dll_CloseHandle]
xor edi, edi
mov ebx, edi
mov ebp, ebx
jmp 0x403edc
cmp dword [0x46d134], 0
je 0x403fb3
lea eax, [esp + 0x18]
push eax
push 0x28
call dword [sym.imp.KERNEL32.dll_GetCurrentProcess]
push eax
call dword [sym.imp.ADVAPI32.dll_OpenProcessToken]
test eax, eax
je 0x403f79
lea eax, [esp + 0x20]
push eax
push str.SeShutdownPrivilege
push edi
call dword [sym.imp.ADVAPI32.dll_LookupPrivilegeValueW]
push edi
push edi
push edi
lea eax, [esp + 0x28]
mov dword [esp + 0x28], 1
push eax
push edi
push dword [esp + 0x2c]
mov dword [esp + 0x40], 2
call dword [sym.imp.ADVAPI32.dll_AdjustTokenPrivileges]
push 4
call fcn.00406dcf
mov esi, eax
mov ebx, 0x80040002
test esi, esi
je 0x403f9f
push ebx
push 0x25
push edi
push edi
push edi
mov ecx, esi
call dword [0x4092c8]
call esi
test eax, eax
je 0x403fac
push ebx
push 2
call dword [sym.imp.USER32.dll_ExitWindowsEx]
test eax, eax
jne 0x403fb3
push 9
call fcn.0040156e
cmp dword [0x46d14c], 0xffffffff
cmovne ebp, dword [0x46d14c]
push ebp
jmp 0x403ef8