Why Voldemort doesn't challenge Dumbledore?

[Adrienne Williams]

No: HPFGUIDX 29143

I was reading a fanfic, and a sudden thought hit me: why doesn't
Voldemort challenge Dumbledore? Jo is always saying that Hogwarts is
the safest place because Voldemort wouldn't dare face Dumbledore, but
why? Do y'all have any theories on that?

I know this question has probably been asked before, but I wanted
someone elses view, and in every other group I'm in, this would be
considered OT. Sorry if I'm breaking any of the Commandments. ;)

DRI

<Yes, I am a lurker on this group. I haven't posted here in who knows
how long!>