Thank you. Receiving Emails which are responses to my message(s). For business I need to save messages (many are in a long conversation). It is impossible for me to keep track (I have to open and read each one them), if responder changes what we are discussing but not the subject field, which is very common. Hope this makes sense, my apologies if not.
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J Wilson
There is no way to change the subject in an email you received. It will always show you the original subject line as composed by the sender.
So it sounds like maybe you need to either use mailbox folders or some way to link these message together. Creating a new folder every time you have this situation may lead to a lot of folders if you need this often.
Maybe it is time to turn to a third-party add-on. Something like Mail Tags or Mail Act-On, both from SmallCubed? That may get you what you want.
Another option is to export this messages into Finder folders like I show in a recent video. Or, even print them as PDF files. In fact, if you only need to do this once a series of emails is complete, then selecting them all and printing them as a big PDF may be a great option.
Thank you!