OK, I'm not sure about this - there is some discussion in the MS
Knowledgebase of a hotfix and a fix in Word 2003 SP1 which involves a
registry entry called DefaultCPG which lets you specify the "code page"
(i.e. encoding" that you want Windows to assume if you don't specify
anything else). However, I can't work out exactly what has been fixed in
which version or whether it would help you. You can find more info. at

http://support.microsoft.com/kb/834948/en-us

- it may be worth trying to create and set the registry entry to see what
happens.

Otherwise, I think you have to consider opening the file using a Word macro
(say) and saving it using an unambiguous encoding such as UTF-8 or (safer,
usually) saving it as a Word file. SOme code you could use...

Some sample conversion macros...

Sub ConvertToUTF8()
' convert to a UTF8 format text file

' Needs error checking etc.
Dim oDoc as Word.Document

' change msoEncodingWestern to be the encoding you need. I think this should
work.

Set oDoc = Documents.Open("the path name of the file you need to
convert.txt", _
 False, , False, , , , , , _
 wdOpenFormatEncodedText, _
 msoEncodingWestern, _
 False, False, , True)

' Several of the parameters here are optional or
' irrelevant - you can probably remove the lines from
' ReadOnlyRecommended to SaveAsAOCLetter

oDoc.SaveAs _
 FileName:="the path name of the file to convert to.txt", _
 FileFormat:=wdFormatUnicodeTex­t, _
 AddToRecentFiles:=False, _
 ReadOnlyRecommended:=False, _
 EmbedTrueTypeFonts:=False, _
 SaveNativePictureFormat:=False­, _
 SaveFormsData:=False, _
 SaveAsAOCLetter:=False, _
 Encoding:=msoEncodingUTF8, _
 InsertLineBreaks:=False, _
 AllowSubstitutions:=False, _
 LineEnding:=wdCRLF

oDoc.Close Savechanges:=False
Set oDoc = Nothing
End Sub

or

Sub ConvertToWord()
' convert to a Word document file

' Needs error checking etc.
Dim oDoc as Word.Document

' change msoEncodingWestern to be the encoding you need. I think this should
work.

Set oDoc = Documents.Open("the path name of the file you need to
convert.txt", _
 False, , False, , , , , , _
 wdOpenFormatEncodedText, _
 msoEncodingWestern, _
 False, False, , True)

' Several of the parameters here are optional or
' irrelevant - you can probably remove the lines from
' ReadOnlyRecommended to Encoding

oDoc.SaveAs _
 FileName:="the path name of the file to convert to.doc", _
 FileFormat:=wdFormatDocument, _
 AddToRecentFiles:=False, _
 ReadOnlyRecommended:=False, _
 EmbedTrueTypeFonts:=False, _
 SaveNativePictureFormat:=False­, _
 SaveFormsData:=False, _
 SaveAsAOCLetter:=False, _
 Encoding:=msoEncodingUTF8, _
 InsertLineBreaks:=False, _
 AllowSubstitutions:=False, _
 LineEnding:=wdCRLF

oDoc.Close Savechanges:=False
Set oDoc = Nothing
End Sub

Peter Jamieson