A customer of mine has also encountered this error recently. This might not be related to the old posts @DrH encountered.   I will try to contact support later, but I thought I should comment here.

haha you probably haven't expected an answer by now, but I have one; I once asked a developer for another product ( I don't remember which ) and they said that many installers uses "Program files x86" mostly for backward-compatibility reasons.   I'm ...