I have designed a code for an application where the functionality is to send mails to external and internal (domain) users. There is a style associated with that mail going out. Internal users (within the domain) are able to receive the mails with all the styles in the mail whereas external users (ex: abc@yahoo.com) are not able to receive those styles. They are just receiving the mails in the form of plain text.
I need to send these external mails as well with the styles associated in those mails.