Follow these steps:
'Created by Bill Manville
'
'To create a blinking cell:
'
'If you define a new Style (Format / Style / Flash/ Add ) and apply
'that style to the cells you want to flash, paste the following code
'into a module sheet and run the procedure Flash from Auto-Open if
'desired you will get the text flashing alternately white and red.
Dim NextTime As Date
Sub Flash()
NextTime = Now + TimeValue("00:00:01"

With ActiveWorkbook.Styles("Flash"

.Font
If .ColorIndex = 2 Then
.ColorIndex = 3
Beep
Else: .ColorIndex = 2
End If
End With
Application.OnTime NextTime, "Flash"
End Sub
Sub StopIt()
Application.OnTime NextTime, "Flash", schedule:=False
ActiveWorkbook.Styles("Flash"

.Font.ColorIndex = xlAutomatic
End Sub
Run the StopIt sub to stop the text blinking
HTH Rgds
~Geoff~