Microsoft has released a fix for the Unknown Switch Argument Opening Danish Word 97 Document problem

SYMPTOMS
After you use English (US) Word 2000 to open and update a Danish Word 97 document that contains fields, the following error message may appear in your Word document:

Unknown switch argument

CAUSE
This problem occurs because the field switches contained in the fields in the document are in Danish and are not translated into English (US).

NOTE : Danish Word 97 uses English (US) field names but Danish field switches.

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