> I created a new contacts "folder" in my exchange mailbox and need to
> delete the old (default) one, but the appropriate button is greyed
> out.
You can't delete default folders.
> My question is how I can bypass that and how I can make the new
> folder the default for all uses in outlook.
Not possible.
> I created a new folder
> because I was unable to rename the old folder (same reason: button
> greyed out). So if somebody knows how I can rename the default
> folder, my problem was solved, too.
You can't do that, either. State you goal and maybe someone will be able to
suggest an alternative approach.

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Brian Tillman