How to fix “Error 619”?

Hi,
I have been trying to connect to the Internet for almost a day but, it was to no avail. I receive a pop up on my desktop Which says "ERROR 691". The Error however, occurs only when I try to connect to the Internet. I tried rebooting my modem but, its of no help.
I also tried to enter the user name and password more than once, to ensure that I have entered the correct user id and password, but my internet fails to connect.
Thanks,
Arul

Error Connecting to BSNL Dataone
Verifying username and password…
Error 681: Access was denied because the username and/or password was invalid on the domain.
Redial = 48 Cancel More Info
