Hi guys,
I'd like to mention a point I offered some time ago. 'To whom it may concern' is so rarely used that I don't remember the last time I ever used it. Perhaps half a dozen times in my entire life. Other people have also noted that in this thread that it is not often, even rarely, used, but I feel that readres may be overlooking this advice.
There seems to be so much interest in this phrase that I am concerned that English learners are going to start large numbers of letters in a way that is totally inappropriate.
Best wishes, Clive