Not sure I understand 100% your question. When you delete an email in Outlook, it will be moved to your deleted items folder. When you delete it from the deleted items folder, it will remain for 15-30 days if you're connected to a corporate email server how that setting is set by the system administrator.
If you're using Outlook at home and NOT connected to Microsoft exchange, your email is usually stored in a PST file and you can recover the emails however it's not easy.
Here is a guide for corrupting a PST file and recovering the email using SCANPST - http://www.groovypost.com/forum/microsoft-office/how-to-corupt-an-outlook-pst-file-to-recover-delete-email-t95682.html
Hope that helps.
answered Apr 10 '12 at 21:26
And if your question is about Gmail, then the answer is one month.
answered Apr 16 '12 at 03:32
For outlook, i think it stays there till you manually delete the emails from outlook deleted items folder
answered Jun 04 '12 at 03:57