error messages in dashboard login

See WordPress Administration over SSL page. In there, it says :

The constant FORCE_SSL_LOGIN can be set to true to force all logins to
happen over SSL. This (and all other such definitions) must be placed
before

/* That's all, stop editing! Happy blogging. */

in the file, otherwise
they will not take effect.

I encountered the same problem and moving the code to above the line :

/* That's all, stop editing! Happy blogging. */

in wp-config.php solved the problem.