I'd say that you are using a 'classic RS232 interface' as opposed to a 'Serial TTL-level' interface.
Classic RS232 uses biploar signal levels of plus and minus 3-15v
Serial TTL uses unipolar signals of 0-3v
They are not signal compatible.
The simplest solution is a 'USB to serial TTL convertor', can be had for a few $ or £ in ebay etc in large numbers.
Oh, and by the way, PuTTY has a really good rollback buffer that can be copied to the clipboard as text, easier for you and easier for us. Click the top left corner for the menu.