When You open your database, you can set default prcedure to find out which day is today:
1) in AutoExec macro
2) in load procedure for form
Private Sub Form1_Load()
Select Case DatePart("d", Date)
Case 5
MsgBox "Time to send report!", vbInformation, Date
Case Else
MsgBox "Have a nice day!", vbInformation, Date
End Select