Occasionally, because of a font setting the first letter of a password
gets capitalised so you could try typing the first letter twice and deleting
the first of these.
A new possibility is that you now need an eight letter/digit password
and seven letter/digit passwords are not being recognised.
If not
then try:
In your pc try going to the bottom of your Inbox page and Last Account
Activity - Close all other Activities and then sign out of Gmail including the
iGoogle page.
If you have a removable battery pull this and give it as much time as
you can spare before putting it back in and allowing the reboot. Try signing in
now retyping in your full address including the correct Gmail/Googlemail. com
and the password making sure it is exactly correct. Might take a couple tries
but it should get there as this works for most applications.
One further problem could be if your keyboard is set to the wrong
language which needs to be the same as when you originally created the account.
This can be caused through an OS update.