How to resolve error "Access is denied for root@localhost error" in phpMyAdmin and SqlYog (Windows 7)

I have installed xampp and sqlyog, but when I try to open xampp phpMyAdmin gives me this error:

1045 - Access denied for user 'root'@'localhost' (using password: NO) Connection for controluser as defined in your configuration failed.

When I try open SqlYog, it also shows an 开发者_开发问答error:

Error No :2003 Can't connect to MySql Server on localhost(10061)

How do I resolve errors?

The error no 2003 is described in Webyog FAQ here, please go through this: http://www.webyog.com/faq/content/23/15/en/error-no-2003-can_t-connect.html

And, error 1045 is the the most common authentication error : http://webyog.com/faq/content/23/18/en/error-no-1045-connection-denied.html (if this is the problem then first check that the user is allowed to connect from remote hosts. User should be defined as 'user'@'%' and not 'user'@'localhost')

Given that SqlYog seems to be a commercial software, I haven't used it. But looking at their site I found this in their FAQ - http://www.webyog.com/faq/category/16/how-does-sqlyog-connect-to-mysql.html . Hope it helps.