You'd have to use a macro.
Saved from a previous post:
Option Explicit
Sub testme01()
Dim FoundCell As Range
Dim FindWhat As String
Dim WithWhat As String
FindWhat = "ASDF"
WithWhat = "qwer"
Do
Set FoundCell = ActiveSheet.Cells.Find(What:=FindWhat, _
After:=ActiveCell, _
LookIn:=xlComments, LookAt:=xlPart, SearchOrder:=xlByRows, _
SearchDirection:=xlNext, MatchCase:=True)
If FoundCell Is Nothing Then
Exit Do
Else
FoundCell.Comment.Text _
application.substitute(FoundCell.Comment.Text, _
FindWhat, WithWhat)
End If
Loop
End Sub
application.substitute is case sensitive--so you'll have to match case.
======
If you're using xl2k or higher, you can use replace instead of
application.substitute and that can be made non-case sensitive.
