同一个程序，多次启动，怎么才能知道某次启动的进程唯一性！
用PID的话，也许关掉进程后，再次启动该进程PID可能会一样（虽然这种可能性非常小）
怎样才能知道某个进程的唯一性呢，即使进程名相同，PID相同，我也知道进程是我那次启动的
[解决办法]
再加上进程的启动时间，应该唯一了。
[解决办法]
新建一个clsMutex的类模块

Option Explicit

Private Declare Function CreateMutex Lib "kernel32" Alias "CreateMutexA" (lpMutexAttributes As SECURITY_ATTRIBUTES, ByVal bInitialOwner As Long, ByVal lpName As String) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long

Private Type SECURITY_ATTRIBUTES
    nLength As Long
    lpSecurityDescriptor As Long
    bInheritHandle As Long
End Type

Private Const ERROR_ALREADY_EXISTS = 183&

Private m_hMutex As Long

Public Function CheckMutex(MutexName As String) As Boolean

    Dim s As SECURITY_ATTRIBUTES
    m_hMutex = CreateMutex(s, 0, MutexName)
    
    If Err.LastDllError = ERROR_ALREADY_EXISTS Then
        CheckMutex = False
    Else
        CheckMutex = True
    End If

End Function


Private Sub Class_Terminate()
    CloseHandle m_hMutex
End Sub

然后在主框体引用下就可以保持软件启动的唯一性。。不知道你是不是这个需求。。
'单一实例

Private mut As clsMutex

Private Sub Form_Load()
    '保持单一实例
    Set mut = New clsMutex
    If Not mut.CheckMutex("an unique string") Then End
End Sub