Android : Still have error even though ADT has been updated for Eclipse [duplicate]

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• Update eclipse with Android Development tools 23 28 answers

When I launch Eclipse, I got error as "This SDK requires ADT Version 23.0.0." "Current version is ADT 22". Then I go to Eclipse help->Installed Softwre update, then add the site "http://dl-ssl.google.com/android/eclipse/" Then update the software, but the message comes out as Software being installed. Since being installed, why I still have the message "This SDK requires ADT Version 23.0.0." when Eclipse is launched. How to solve this problem? Thanks