Have the ThisWorkbook Open Event, Select Cell: A1, on the Sheet you want displayed show the Assistant and have the Assistant show your message!
Private Sub Workbook_Open()
'ThisWorkbook code module!
Assistant.Visible = True
With Assistant.NewBalloon
'.Heading = "My Application"
.Heading = " "
'.Heading = Application.Name
.Text = "{cf 252}By:{cf 0} {ul 1}Joe Was, 2/2006{ul 0}"
'.Button = msoButtonSetNone
.Show
End With
Sheets("Sheet1").Select
Sheets("Sheet1").Range("A1").Select
End Sub
Then As an auternative or in conjunction with the above, add the same message to the Validation Box, which will also update the Assistant every time Cell: A1 on that sheet is selected, from the Excel Toolbar: Data - Validation...
Select the: Input Message [Tab]
Add your Title and Message.
Note: The Assistant is Modaless, but when used as a Ballon like the code above it becomesis Modal so it must have a Button. To avois this only use the Sheet & Range code in the above Event and load that cell with a Validation Message and it will be Modaless and not have a Button!
This is the tack I take!