Gmail account exists but doesn't?

I'm having a problem accessing a gmail account I created a while ago. When I enter the password, it says it's incorrect. When I try to go through forgotten password procedure, it says the account doesn't exist. When I try to create an account with that user name, it says it's already taken. What gives? I'll be very highly appreciative for anyone's help with this if there's anything that can be done. Thanks.