In my mail I have created new file folder and now I need to delete the file. How do I delete it.?

There is a help page titled "How can I delete a folder?" located at http://help.yahoo.com/help/us/mail/manage/manage-1... Here is the information from that page:

Only empty folders can be deleted. In order to delete a folder, you must first empty it of all messages.

To delete messages in a folder:

Open the folder, which contains the message to be transferred.

Place a check in the box to the left of the message you would like to delete. To select all messages, just click the "Check All" link at the bottom of the page.

Click the "Delete" button to have all selected messages transferred into the trash folder.

To permanently remove the contents of the trash, click the "Empty" link next to the trash folder in the left navigation bar. Next, you will see a prompt asking if you're sure you want to delete all messages. Click "Yes" to delete or "No" to return to the previous page.

Please Note: Once messages are emptied from the trash folder, they are permanently deleted from the Yahoo! Mail server and cannot be recovered.

Once you have emptied a folder, you can delete it by doing the following:

Click the "Folders" link on the left navigation bar.

On the Folders screen, find the folder you would like to delete and click the "Delete" link located to the right of the folder name.

The name of the folder will then disappear from the list of folders.

Please note: You can't remove or rename the permanent folders in your account. These folders include inbox, sent, draft, and trash.

right click the folder

select delete