Do I just use the Weekday function?

You could do something like this:

Private Sub AppointmentDate_BeforeUpdate(Cancel As Integer)

    If Weekday(AppointmentDate) = 1 Or Weekday(AppointmentDate) = 7 Then
        MsgBox "This is a weekend"
        Cancel = True
    End If
    
End Sub

Thank you I will try It.

I thought that's how you did It. I just didn't know that was the best way. Thanks again

the best way early on is one that works... until you find a better way.

I just thought of another thing I want where you can't make an appointment on weekend, and it has to be between 9 am and 5pm weekdays? I am trying to figure It out for myself.

Hour Minute Second

I am sorry I only need hours and minute. I would like If It after 5PM or before 9 AM it stays on the appointmentdate field.

I have a database with a field name appointmentdate and the before update I put In my code:Private Sub btnSave_Click()

    ' Assuming Appointmentdate is the control on the form
    Dim appointment As Date
    appointment = Me.appointmentdate.Value ' Get the value from the form control

    ' Check if the appointmentdate falls on a weekend (Saturday or Sunday)
    If Weekday(appointment, vbMonday) > 5 Then
        MsgBox "Appointments cannot be scheduled on weekends. Please choose a weekday.", vbExclamation
        Me.appointmentdate.SetFocus ' Set focus back to the appointment date field
        Exit Sub
    End If

    ' Check if the appointment time is outside 9:00 AM to 5:00 PM
    If TimeValue(appointment) < TimeValue("9:00:00 AM") Or TimeValue(appointment) > TimeValue("5:00:00 PM") Then
        MsgBox "Appointments must be scheduled between 9:00 AM and 5:00 PM.", vbExclamation
        Me.appointmentdate.SetFocus ' Set focus back to the appointment date field
        Exit Sub
    End If

    ' If all validations pass, save the record
    DoCmd.RunCommand acCmdSaveRecord

End Sub
It stop at the setfocus. Can someone tell me why?

Because of the Exit Sub.

I would set a flag to determine if the condition has been validated.
Something similar to this:

Details

Private Sub btnSave_Click()

    Dim Appointment As Date, isValidated as Boolean

    isValidated = True

    Appointment = AppointmentDate

    If Weekday(Appointment, vbMonday) > 5 Then
        MsgBox "Appointments cannot be scheduled on weekends. Please choose a weekday.", vbExclamation
        AppointmentDate.SetFocus
        isValidated = False
    End If

    If TimeValue(Appointment) < TimeValue("9:00:00 AM") Or _
         TimeValue(Appointment) > TimeValue("5:00:00 PM") Then
        MsgBox "Appointments must be scheduled between 9:00 AM and 5:00 PM.", vbExclamation
        AppointmentDate.SetFocus
        isValidated = False
    End If

    If isValidated Then DoCmd.RunCommand acCmdSaveRecord

End Sub
Copy

Is the before update the right place to put it?

Can I use a Setfocus In a Date time field? I want to check the time if it after 5PM return to that feild. I have a date field on my form and It set to date/time In the table.