You cannot sync FROM your Android phone to your home PC. You can sync from your Home PC to the phone. If you do not have a Sync account, please read this:

https://support.mozilla.com/en-US/kb/How%20to%20sync%20Firefox%20settings%20between%20computers#Step_2_Set_up_Firefox_Sync_on_other_installations_of_Firefox_

and

http://www.mozilla.com/en-US/firefox/sync/firstrun.html

Thanks, But I have done this and I continue to get "invalid E mail address" when trying to set up a new account. Assume for a moment I somehow already have an account under - [email protected] but have no record of it, therefor can't log in because I don't the know username . what now? I was able to reset my password but have no idea what username to enter. If I do in fact already have an account under [email protected] how can I retrieve my username? I do know the password. Does this clarify my problem?

Three suggestions:

1. Try a different email address to see if that still gives you the error OR

2. Reset your Sync Key (Warning: It will erase all of your data previously synced.) OR

3. Delete your CURRENT Sync account (since you thought you might have one already) and then create a new one using your Roadrunner email address.

I suggest you backup your bookmarks and passwords just in case.

1. 1 tried another e mail address. The error message pops up after only 2 or3 letters entered, NO MATTER WHAT letters are entered.

#2 I will try to reset my sync key if I can figure out how.
#3 How does one delete a current sync account? I sure don't want to loose my bookmarks or passwords. I do have 2 other lap top computers synced with X marks so all of my desktop Firefox bookmark and passwords are on those Firefox browsers too. 
     To review I do use X marks on my desktop and other laptops but I don't think X marks will sync to Firefox mobile android, which is why I tried to use Firefox sync tool. Thanks for your patience.

To delete the Sync Account, go to this site:

https://account.services.mozilla.com/

You will not lose your bookmarks or passwords if you delete your sync account. But things can happen without any reasons, that's why I suggest you to backup your bookmarks and passwords just in case.

Xmarks does not sync to your phone. But you can install its Premium version in the Market, the same goes for LastPass (for Passwords).

FYI , When ever I go to tools, set up sync, create new account, get the screen and type in just ONE letter in the e mail line I get the invalid message.If I click on "connect" I get a add device screen. Or if I go to options it asks me to " set up Firefox sync" click on that and I go back to the set up account screen. For me it's a catch 22. All I do is go in circles. I'm going to now go to account services, try to cancel the account, if there is one and start over. Please stand by

If you cannot delete your account, try to start your Firefox in SAFE MODE:

http://support.mozilla.com/en-US/kb/Basic%20Troubleshooting#w_4-restart-firefox-in-safe-mode

Maybe one of your add-ons is causing the problem.

If that does not detect any add-on problem, try to create a new Profile:

https://support.mozilla.com/en-US/kb/Managing%20profiles

So I tried to reset my password on the sync account services page and it basically tells me they don't know who I am. I take this to mean, as I thought, I don't have an account. Which takes me back to setting up an account and this page will not let me enter an e mail address with out the pop up the error message. I have even rebooted Firefox to no avail. Thanks so much for trying to help me but I really don't know where to go from here.I would like to think I am just doing something wrong but after so may repeated tries I really think this is a Firefox problem.

I will try one more time. Thanks