1. open a cmd prompt and type ipconfig for each windows machine; in debian, open a terminal and type ifconfig eth0
all your addresses must be in the same range, & judging by what you've listed they...

you can set you client (outlook in this case) to

"leave a copy of the message on the server"

tools, email accounts, view or change, change, more settings, advanced tab.

do this on every...

if running a continuous ping brings concerns about performance, wait till you collect traffic with wireshark!
you will fill your hard drive in a day or two.

as said above,

most every pc / laptop has a cmos reset jumper.
this will absolutely clear any password.
the jumper is almost always near the cmos battery.
on a laptop... search the d610 pdf.

google is my friend.

open the case.
unplug =everything=
blow out the dust, dirt, & small animals
firmly reseat everything
try again.
(stuff needs reseated because as the pc warms then cools, the expansion /...

often the admin is the only person in an organization with the technical knowledge to do his job and as long as things run smoothly, everyone (rightly so) is happy.

the admin reports to or is the...