Last few days when i was opening my blog it is showing a window asking for Username and Password
A Username and Password are being requested by http://bloggerblogwidgets.googlecodes.com. The site say:"Google Code Subversion Repository "
Just as shown in the image below
Why This Problem Occured
Because my Recent comments widget was having a link from the http://bloggerblogwidgets.googlecodes.com. and this site is under maintenance, so it is showing this error
Solution for This
Go to Layouts and Remove the Gadgets of Recent Comments.
Now I checked the Blog again it is working fine without and window asking for Username and Password,
If you are having any codes from this site remove that widget and check it, I am sure your problem will be solved