A user name and password are being requested by http://:. The site says: “XDB” in Oracle APEX

Hi,
After Installation Oracle Apex, whenever I tried to connect in Oracle APEX environment with following URL

http://localhost:8080/apex  

It was saying -
A user name and password are being requested by http://:. The site says: “XDB”    (In apex version 4.2.4 and Oracle Database version 10g Enterprise Edition Release 10.2.0.5.0 - 64bits.)


Solution was: 
1) Log in with sys user then
2) unlock and change the XDB user's password and provide these when it will ask

SQL> Alter user xdb identified by xdb account unlock ;

3) Then invoke this URL  http://localhost:8080/apex    
It will ask for user id and password. please provide this here. 

user id : xdb
password : xdb


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