My windows mail app is partially in Chinese

Some of the mail I recieve is partially in Chinese, usually where one of the Norwegian special characters (æ, ø, å) are supposed to be, but then it also changes some of the letters before or after the special characters. Norwegian is my main language in windows with English as the second language and chinese is no where to be found on the list. It seems like I've always got this problem with the same companies i recieve advertisements from. Any ideas what I can do about this? I'll include a screenshot for reference.