Fail to open connection to MySQL with physical ip.

[Joe Hsu]

My program and MySQL are in the same machine.
I used the ip of the local area connection (physical ip) and root account to open mysql connection, as follows.

================================================
string connStr = "server=10.36.63.202;uid=root;pwd=123";
MySqlConnection conn = new MySqlConnection(connStr);
try
{
conn.Open();
}
catch (MySql.Data.MySqlClient.MySqlException ex)
{ // Got error code: 1045 }
================================================

I always got the error code 1045. (invalid username and password)
If I changed server to "localhost" or "127.0.0.1", it always worked.
If I used this root account to open mysql in command line (mysql -u root -p), it always worked too.
Why couldn't I use physical ip to open mysql connection?
Thanks.