first time login does not work

Hi All,

In my login aspx page i have two languages "English" and "Hindi" buttons.

When i click on English, the page display in English language. Here i am getting problem with login. When i enter username and password and press enter key than it does not work only for the first time. It works fine from second time.

When i click on Hindhi, the page display in Hindi language. When i enter username and password and press enter key than it does not work for the first time. It works fine from second time.

What could be the problem?

Thanks in advance,
Darma