Here is a solution my husband came up with.
You asked:
I have been looking into how to distinguish the mail when it comes
into the inbox by color; I have three email accounts and even
though the mail does go into its respective folders, they all also
go into the inbox. It would be helpful because when anyone sends
me something from my web page at www.zeli.net it goes to a seperate
email address and I would be able to find them faster in the nbox
without going to the respective mailbox. I don't know if this is
possible as I didn't see that under the color coding in the prefs,
but thought I would ask.
One way to achieve this is to set up a "rule" to handle such messages.
First, select a message of this sort in your Inbox. Then go to Mail
Preferences (command-comma) and click on the Rules tab. Click on the
Add Rule button.
Give the rule a meaningful name (overtyping the Rule Number), then
click on the first condition pop-up button (set to "From:" by
default), changing it to "To:" or "Any Recipient:"
The second pop-up button should be left at "Contains", while the
next text field should already contain the destination e-mail address.
Navigate to the first action pop-up button (default value "Move
Message") and reset it to "Set Color of Message". Leave the middle
pop-up at "of background" as this will stand out much more clearly
than changing the text colour. Then pick a colour to suit yourself
from the third pop-up button. If you don't like any of those on
offer, then clicking on "Other…" will display the OS X Color Picker
and allow you to set the precise shade you want.
Then click on OK. Mail will offer to apply your new rule to messages
in open mailboxes. Do this if you feel like it—it can be a useful
test. Alternatively, you can select any message in your inbox and
summon a contextual menu, then pick "Apply Rules".
In any case, all subsequent messages addressed to that particular
recipient will have a coloured background. You can add more criteria
at any time by repeating the process and clicking the Edit button
instead of Add Rule, then clicking the little plus sign to the right
of the criterion field.
HTH
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No faith can ever be refuted by reality, let alone by arguments.
Gerd Lüdemann