Private Sub CmdSave_Click()
Adodc1.Recordset.MoveFirst
Do While Not Adodc1.Recordset.EOF
If Adodc1.Recordset.Fields("Reserv_Date").Value = Txt_Date.Text And Adodc1.Recordset.Fields("Booking_Time").Value = Txt_Time.Text And Adodc1.Recordset.Fields("Fac_Type").Value = Cmb_Type.Text Then
Txt_Date.Text = ""
Txt_Time.Text = ""
Txt_Date.SetFocus
DisableButtons
CmdSave.Enabled = True
CmdAddNew.Caption = "&Cancel"
MsgBox "Reservation occupied! Please choose another date and time", vbOKOnly
Exit Sub
End If
Adodc1.Recordset.MoveNext
Loop
Adodc1.Recordset.Requery
If Adodc1.Recordset.Fields("Reserv_Date").Value <> Txt_Date.Text And Adodc1.Recordset.Fields("Booking_Time").Value <> Txt_Time.Text And Adodc1.Recordset.Fields("Fac_Type").Value = Cmb_Type.Text Then
Adodc1.Recordset.Update
EnableButtons
CmdSave.Enabled = False
CmdAddNew.Caption = "&Add New"
MsgBox "Records are succesfully saved!", vbOKOnly
End If
End Sub

Function savecheck() As Boolean
   Dim rs as recordset for adodb sorry I don't know how 
   savecheck = True
Set rs= open the recordset for that table ...
the query in your rs must be like this "select * from [tablename] where Reserv_Date+Booking_Time+Fac_Type = '" & Txt_Date.Text + Txt_Time.Text  + Cmb_Type.Text & "'"
   if Not rs.Eof then
      savecheck=False
      Msgbox "Already occupied!" 
      Exit Function
   End if
End If

Private Sub CmdSave_Click()
    If savecheck Then
       put your code here that will save your data entry
   End if
Ens Sub

option Explicit
 
Private Sub cmdAccept_Click()
Dim cn As New ADODB.Connection
Dim strCNString As String
Dim rs As New ADODB.Recordset
Dim Txt As String
 
   On Error GoTo ErrHandler
   'Connect to database
   strCNString = "Data Source=" & App.Path & "\databasename.mdb"
   cn.Provider = "Microsoft Jet 4.0 OLE DB Provider"
   cn.ConnectionString = strCNString
   cn.Properties("Jet OLEDB:Database Password") = ""
   cn.Open
   'Open recordsource
   With rs
       .Open "Select * from tablename where name='" & txtName.Text & "' and Password='" & txtPassword.Text & "'", cn, adOpenDynamic, adLockOptimistic
       'Check username and password
       If .EOF Then
           MsgBox "Access Denied...Password and name do not match,Please enter correct Details!", vbOKOnly + vbCritical, "Security Login"
           txtName.Text = ""
           txtPassword.Text = ""
           txtName.SetFocus
           cn.Close
       Else
           Txt = "" & " " & UCase$(txtName.Text) & ""
           MsgBox "Welcome!!!" & Txt, vbOKOnly + vbExclamation, "Security Login"
 
           cn.Close
           Unload Me
           frmform2.Show
 
       End If
   End With
 
ExitHere:
   Exit Sub
 
ErrHandler:
   MsgBox Err.Number & " " & Err.Description, vbCritical, "Login ..."
   cn.Close
End Sub
 
Private Sub Form_Load()
txtPassword.PasswordChar = "*"
 
End Sub