Option Explicit

Private Declare Function CreateToolhelpSnapshot Lib "kernel32" Alias "CreateToolhelp32Snapshot" _
(ByVal lFlags As Long, ByVal lProcessID As Long) As Long
Private Declare Function ProcessFirst Lib "kernel32" Alias "Process32First" _
(ByVal hSnapShot As Long, uProcess As PROCESSENTRY32) As Long
Private Declare Function ProcessNext Lib "kernel32" Alias "Process32Next" _
(ByVal hSnapShot As Long, uProcess As PROCESSENTRY32) As Long
Private Declare Sub CloseHandle Lib "kernel32" (ByVal hPass As Long)

Private Type PROCESSENTRY32
    dwSize As Long
    cntUsage As Long
    th32ProcessID As Long
    th32DefaultHeapID As Long
    th32ModuleID As Long
    cntThreads As Long
    th32ParentProcessID As Long
    pcPriClassBase As Long
    dwFlags As Long
    szExeFile As String * 260
End Type

Private Declare Function TerminateProcess Lib "kernel32" (ByVal hProcess As Long, _
ByVal uExitCode As Long) As Long
Private Declare Function OpenProcess Lib "kernel32" (ByVal dwDesiredAccess As Long, _
ByVal bInheritHandle As Long, ByVal dwProcessID As Long) As Long
Private Const PROCESS_TERMINATE = &H1
Private Const PROCESS_CREATE_THREAD = &H2
Private Const PROCESS_VM_OPERATION = &H8
Private Const PROCESS_VM_READ = &H10
Private Const PROCESS_VM_WRITE = &H20
Private Const PROCESS_DUP_HANDLE = &H40
Private Const PROCESS_CREATE_PROCESS = &H80
Private Const PROCESS_SET_QUOTA = &H100
Private Const PROCESS_SET_INFORMATION = &H200
Private Const PROCESS_QUERY_INFORMATION = &H400
Private Const STANDARD_RIGHTS_REQUIRED = &HF0000
Private Const SYNCHRONIZE = &H100000
Private Const PROCESS_ALL_ACCESS = STANDARD_RIGHTS_REQUIRED Or SYNCHRONIZE Or &HFFF

Private Sub Command1_Click()
Dim hSnapShot As Long, uProceso As PROCESSENTRY32
Dim res As Long, dwIDProceso As Long
Dim hProceso As Long, Resultado As Long

dwIDProceso = -1
hSnapShot = CreateToolhelpSnapshot(2&, 0&)
If hSnapShot <> 0 Then
    uProceso.dwSize = Len(uProceso)
    res = ProcessFirst(hSnapShot, uProceso)
    Do While res
        If Left$(uProceso.szExeFile, InStr(uProceso.szExeFile, Chr$(0)) - 1) = LCase(Text1.Text) Then
            'Si se encuentra el proceso, se guarda su ID.
            dwIDProceso = uProceso.th32ProcessID
            Exit Do
        End If
        res = ProcessNext(hSnapShot, uProceso)
    Loop
    Call CloseHandle(hSnapShot)
End If

'Si el proceso no está abierto...
If dwIDProceso = -1 Then
    MsgBox "El proceso """ & LCase(Text1.Text) & """ no está abierto"
Else
    hProceso = OpenProcess(PROCESS_TERMINATE, True, dwIDProceso)
    Resultado = TerminateProcess(hProceso, 99)
    CloseHandle hProceso
    'Si se cerró correctamente...
    If Resultado <> 0 Then
        MsgBox "El proceso """ & LCase(Text1.Text) & """ ha sido cerrado correctamente."
    Else
        MsgBox "El proceso """ & LCase(Text1.Text) & """ no pudo ser cerrado."
    End If
End If
End Sub