Public Class Form1
    Public Property ToolTipIcon As ToolTipIcon
   

    Sub connect()
        acsconn.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=D:\DB\База данных8.accdb;Persist Security Info=False;"
        acsconn.Open()
    End Sub

    Sub fillcombo()
        strsql = "select distinct * from Таблица1"

        Dim acscmd As New OleDb.OleDbCommand
        acscmd.CommandText = strsql
        acscmd.Connection = acsconn
        acsdr = acscmd.ExecuteReader
        While (acsdr.Read())
            ComboBox1.Items.Add(acsdr("Исполнители"))
        End While
        acscmd.Dispose()
        acsdr.Close()
    End Sub

    Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ComboBox1.SelectedIndexChanged
        'strsql = "select distinct* from Таблица1 where Исполнители ='" & ComboBox1.Text & "'"

        strsql = "SELECT DISTINCT Таблица1.Исполнители FROM Таблица1"

        'strsql = "select DISTINCT Исполнители from Таблица1 where Исполнители ='" & ComboBox1.Text & "'"

        Dim acscmd As New OleDb.OleDbCommand
        acscmd.CommandText = strsql
        acscmd.Connection = acsconn
        acsdr = acscmd.ExecuteReader
        acscmd.Dispose()
        acsdr.Close()
    End Sub

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        ToolTip1.ToolTipIcon = Windows.Forms.ToolTipIcon.Info
        ToolTip1.ToolTipTitle = "Подсказка"
        ToolTip1.SetToolTip(ComboBox1, "Выбор исполнителя.Должны Отображаться уникальные значения")
        Module1.connect()
        Me.fillcombo()
    End Sub

End Class

strsql = "SELECT DISTINCT [Исполнители] FROM Таблица1"

strsql = "SELECT DISTINCT Таблица1.Исполнители FROM Таблица1"

Private Sub Form_Open(Cancel As Integer)
    [ПолеСоСписком0].RowSource = "SELECT First(Таблица1.[id]) AS [id поле] FROM Таблица1 GROUP BY Таблица1.[id];"
End Sub

        Using conn = New System.Data.OleDb.OleDbConnection()
            conn.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=D:\DB\База данных8.accdb;Persist Security Info=False;"
            conn.Open()
            Using cmd = conn.CreateCommand
                cmd.CommandText = "SELECT DISTINCT Таблица1.Исполнители FROM Таблица1 "
                Dim dt As New DataTable
                dt.Load(cmd.ExecuteReader)
                ComboBox1.DataSource = Nothing
                ComboBox1.ValueMember = ""
                ComboBox1.DisplayMember = ""
                ComboBox1.DataSource = dt
                ComboBox1.ValueMember = "Исполнители"
                ComboBox1.DisplayMember = "Исполнители"
            End Using
        End Using

ComboBox1.DataSource = Nothing
                ComboBox1.ValueMember = ""
                ComboBox1.DisplayMember = ""