在电子邮件中显示正确特殊字符的问题

I have a PHP file that generates an automatic email. Inside this email, there are special characters like this (ä,ö,ü) that don't show correctly. They are replace by a question mark.

Can someone help me in this? What can I change inside my PHP code?

This is the PHP file: click here

thats how the email looks

Set the email header to UTF8 Charset

mail($to,$subject,utf8_decode($message),$from."
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
");

This will solve the problem.

This has already been posted previously on stack overflow on below link.

php mail special characters utf8

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