Although the N810 Email Application works great for me with other accounts, it will not work with GMAIL. On IMAP, it will only download headers and not messages. On POP it completely erratic.
I did read that others were having this problem.
Has anyone solved it?

Check Modest out, a beta has just been released. (The old email client won't handle Gmail-IMAP)

Yeah, from what I can tell it's a common problem with the included email. ClawsMail seems to solve the problems for some, though I haven't gotten it working 100% for me.

OK, thank you both. i just installed Modest and so far, so good.
By the way, I am very happy with the N810.

Got this from a thread @Brighthand started by user Ed Hardy:

POP3

If you want to be able read and respond to your emails when you're offline, you can download then with the basic POP3 service. This is convenient, but the setup process is not. Here are the settings I used:

Account Name: (Something like Personal or Gmail)
Account Type: POP3

Hit Next

Name: (The name you want to be on your outgoing emails)
User name: XXXXXXX@gmail.com
Password: *******
E-mail Address: XXXXXXX@gmail.com (same as User Name)

Hit Next

Incoming server: pop.gmail.com
Outgoing server: smtp.gmail.com
Use connection-specific SMTP servers: No (Don't hit the check mark)

Hit Next

The next page tells you setup is complete, but it's not. Hit the button labeled "Advanced".

On the Incoming Tab
Retrieve: (Your choice)
Leave Messages on server: (You probably want to select this, or you won't
be able to read your messages online any more)
Password authentication: Normal
Security: SSL (POP3S)
Incoming e-mail port: 995

On the Outgoing Tab:
SMTP authentication: Login
User name: XXXXXXX@gmail.com
Password: *******
Security: SSL
Outgoing e-mail port: 465

Hit OK

Hit Finish


IMAP

I briefly set up Gmail's IMAP service, but quickly switched back to POP3. It was painfully, agonizingly slow. Opening each message required the N810 to go to Google servers and this took minutes every time.

Unless someone else with a better experience can chime in, I'd suggest you avoid using this service.


Setting for POP3 and IMAP

Open the Drop-down box, pick Tools, then Settings.

Update automatically: (I have this turned off, because there's no way
to set the times when you'll get messages. I got tired
of being woken up at midnight with a new email.)
Update when connected via: (this is handy)
Update Interval: (Your choice, but keep in mind frequent updates
will affect your battery life.)

The included email app DOES work with Gmail for me.

In fact being the default email app, it also alerts me (flashing LED) wherever there is a new email (which Claws doesnt do).

Follow the above post - the main thing being setting up the correct incoming and outgoing posrts with SSL for gmail to work.

I got the thing setup right, but under IMAP (as noted) it apparently doesn't download the actual message, just the header. This is unacceptable. What's the point of having an email client if I have to go online to get the email anyway? I might as well just use the browser! And POP isn't really as useful - it means all the messages on the server are not marked as read or replied-to or deleted. So you quickly lose track of continuity if you're using the web client intermittently.

Plus my email program only launches 1/5 times and does not seem to auto launch unless it wants to. If it's not reliable, I can't use it. I don't know if this is particular to the N810 though, so my experience may be different than others.

on my 810 the built in mail app works well for gmail pop and not for imap
with modest (which i just downloaded last nite) gmail imap works fairly well for a BETA app
i plan to use modest when i have wifi access and the builtin when i have to use my evdo connection

OK, I spoke too soon. Modest retrieves Gmail IMAP fine, but does not send for me.
I am having such a good time with the N810. If I could just solve this problem, I would be very happy.

Check with the settings as noted above

On the Outgoing Tab:
SMTP authentication: Login
User name: XXXXXXX@gmail.com
Password: *******
Security: SSL
Outgoing e-mail port: 465

I use Gmail for sending with no problem.