Hi, 

I am new to Salesforce.com and just going through short language examples (in chap2 of APEX workbook) with Developer Console. Somehow I got DUPLICATE_VALUE: Failed to create createContainerMember for containerId=..." when the console kicks off. I also got  METHOD_NOT_ALLOWED "Unable to delete container member undefined: HTTP Method 'DELETE' not allowed....".

I am using Google Chrome on Windows 7. Please advise. Thanks!