1) it's huge
2) it's private
and
3) I no longer have a copy of it
but that shouldn't matter - the contents are type "ZIP archive", and it seems to be just the name which was confusing things. Maybe there was a non-ASCII character in its name - it was on a shared drive on a Czech copy of Windows.
Sorry, I can't attach it because:
1) it's huge
2) it's private
and
3) I no longer have a copy of it
but that shouldn't matter - the contents are type "ZIP archive", and it seems to be just the name which was confusing things. Maybe there was a non-ASCII character in its name - it was on a shared drive on a Czech copy of Windows.