When looking at my folder list, I see 2 folder sets with the same emails. One is my default where I keep all my email, contacts, etc… and the second one is called Personal Folders and shows all my emails as well.

When I delete a message from Personal Folders, it is also deleted from my main mailbox.

How can I remove this duplicate set of folders?

When I receive an email from a certain contact, can I get a different “new email” sound than the default?

I sometimes receive a mailing which shows “Undisclosed Recipients” in to To field. I want to send out a mailing myself now.
How can I also send out with “Undisclosed Recipients”?

When I close a message, I often get this question. I’m not aware of making any changes to it.
What changes is it trying to save and how do I get rid of it?

When starting Outlook, every time I need to go through some installation process before it actually opens. Sometimes this also happens when I open a message or do something else.
Why is Outlook doing this and how can I make it go away?

Whenever I open up Outlook, I get a dialog box asking for Microsoft LDAP Directory settings for port 3286.

What do I need to fill in here?

The date on my emails is now dd/mm/yyyy, but I want it to be mm/dd/yyyy.

Where do I change that date format?

I am facing an issue where my username automatically appears in the body of any email reply/forward.

Whenever I hit on the spacebar as the first character to start off editing of the quoted email message, my username will appear as [John] in the email message.

Is there any way to turn this off?

Following up on your yesterday’s tip; I attach a file quite often and use some other commands with long keyboard sequences quite often as well.
Is there any way I can do this quicker instead of typing this (not intuitive) keyboard sequence?

The tooltips of some commands do not show their keyboard shortcuts (like for instance “Attach File”).
Do I always have to use my mouse for this or are there any hidden shortcuts for or can I create my own?