I'm not very familiar with the ExportXML method, but there are some basic
VBA syntax errors here - perhaps I can at least help you with those, and if
you still have problems after that, perhaps someone more familiar with the
ExportXML method might like to join in ...
First, a VBA statement must either be all on one line, or you must include
line separation characters - a space followed by an underscore (" _") at the
end of each line except the last. And second, when using named arguments,
you need to use a colon followed by an equals sign (":="). Third, the
ObjectType argument can only accept a member of the acExportXMLObjectType
enumeration, i.e. acExportForm, acExportFunction, acExportQuery, etc., the
addition of the string "PORTABLES ... " etc after acExportForm in the third
line of your code is not valid. And fourth, arguments must be separated by
commas.
Taking into account all of the above, your original code, translated into
valid VBA syntax, would look like this ...
Private Sub Command93_Click()
Application.ExportXML _
ObjectType:=acExportForm, _
DataSource:="PORTABLES DATA ENTRY PAGE", _
DataTarget:="Export.xml", _
PresentationTarget:="Export.xsl"
End Sub