Repeating Microsoft Word VBA until no search results found

Good question this one, you can loop through the whole document using the Selection.Find.Found result.

What you do is start a search and if you find a result go into a loop only while the Selection.Find.Found result is true. Once you've got through these, you're done. The following code should do the trick nicely for you.

Sub SearchFN()
    Dim iCount As Integer

    'Always start at the top of the document
    Selection.HomeKey Unit:=wdStory

    'find a footnote to kick it off
    With Selection.Find
        .ClearFormatting
        .Text = "&&FB:*&&FE"
        .Replacement.Text = ""
        .Forward = True
        .Wrap = wdFindContinue
        .Format = False
        .MatchCase = False
        .MatchWholeWord = False
        .MatchKashida = False
        .MatchDiacritics = False
        .MatchAlefHamza = False
        .MatchControl = False
        .MatchByte = False
        .MatchAllWordForms = False
        .MatchSoundsLike = False
        .MatchFuzzy = False
        .MatchWildcards = True
        .Execute
    End With

    'If we find one then we can set off a loop to keep checking
    'I always put a counter in to avoid endless loops for one reason or another
    Do While Selection.Find.Found = True And iCount < 1000
        iCount = iCount + 1

        'Jump back to the start of the document.  Since you remove the
        'footnote place holder this won't pick up old results
        Selection.HomeKey Unit:=wdStory
        Selection.Find.Execute

        'On the last loop you'll not find a result so check here
        If Selection.Find.Found Then

            ''==================================
            '' Do your footnote magic here
            ''==================================

            'Reset the find parameters
            With Selection.Find
                .ClearFormatting
                .Text = "&&FB:*&&FE"
                .Replacement.Text = ""
                .Forward = True
                .Wrap = wdFindContinue
                .Format = False
                .MatchCase = False
                .MatchWholeWord = False
                .MatchKashida = False
                .MatchDiacritics = False
                .MatchAlefHamza = False
                .MatchControl = False
                .MatchByte = False
                .MatchAllWordForms = False
                .MatchSoundsLike = False
                .MatchFuzzy = False
                .MatchWildcards = True
            End With
        End If
    Loop
End Sub

This can be done without using Do while(lots of extra lines, and space/time wastage), It could be as simple as follows:

Sub SearchFN()

    'Start from The Top
    Selection.HomeKey Unit:=wdStory

    'Find the first search to start the loop
    Do
    With Selection.Find
        .ClearFormatting
        .Replacement.ClearFormatting
        .Text = "&&FB:*&&FE"
        .Replacement.Text = ""
        .Forward = True
        .Wrap = wdFindstop
        .Format = False
        .MatchCase = False
        .MatchWholeWord = False
        .MatchKashida = False
        .MatchDiacritics = False
        .MatchAlefHamza = False
        .MatchControl = False
        .MatchByte = False
        .MatchAllWordForms = False
        .MatchSoundsLike = False
        .MatchFuzzy = False
        .MatchWildcards = True
        .Execute
    End With

    'If we found the result then loop started
    If Selection.Find.Found Then

            '' Do your work here
            ' Always end your work after the first found result
            ' else it will be endless loop

    Else
    'If we do not found any then it will exit the loop
    Exit Do
    End If
    Loop

End Sub