On old stat T8411R have wiring on G, C, R, Y, W2 and E are jumpered, and O - on new RTH6300B have G, W O/B, Y, R, Rc. Were does W2 and O from T8411R go on RTH6300B? I know C does not get used on RTH6300B. Does W2 and O both get wired in together on W O/B port?

Read page 6 of the link below

http://customer.honeywell.com/techli...0s/69-1717.pdf

Here is what it says

Do you have 6 or more wires? If so, stop now.
You may have purchased the wrong replacement

Now I know you really read your install instructions that Honeywell puts in every thermostat box. I guess you were in a hurry and forgot that page probably going right to the wiring diagram. This happens when you are in to big a hurry. This can cause damage to your equipment. Slow down.

Go get a different Honeywell thermostat that will work and have a go at it again.

Thanks for the quick response. I did look at the instructions and read to count the wires coming out of the wall which is 6 and if one is C or C1 then do not count it in the total count which I didn't. If the total (not counting the C or C1 wire) is 5 or less than proceed to next step. This is on page 6. So does this still mean wrong thermostat? I did not count the C wire. Just need clarification. Thanks!

You need the C wire for one leg of the power to the thermostat.
You need a heat pump thermostat with emergency/electric furnace.

For fun I have sent you the diagram of your old thermostst.