I suppose you should be using MS Outlook. If you accidentally emptied Deleted Items folder, there are actually methods to undelete them. One way is to edit Windows Registry, another way is to use a software. See resources for more. Regards.
Once you delete an email, you can go to the "deleted" folder and right-click on the email and choose "move to", then you can move it to any other folder in your email account.
In Windows, normally deleted files are not yet deleted. They are instead shown in the Recycle Bin, which allows users to undelete items before they are permanently lost.
You can recover your file by undelete command: undelete <filename>
Use a undelete program.
Go to the Deleted Items folder and find the deleted Yahoo! mail you want to restore. Click it and choose move to inbox.
There is a folder called deleted items in your menu, that is where your emails go when you delete them, as a side note you should delete the items in the deleted folder every so often to help save space, while in the folder click edit at the top and then click empty deleted items folder.
If it was possible there would be a button for it. Sorry, once a picture is deleted it is gone for good.
If email has been moved into Deleted Items Folders, then user can retrieve back all the email by simply drag and drop because they are soft deleted items. But, in case of hard deletion or you can say that emails have been deleted from Deleted Items Folders, than user should go for any third party utility which can easily restore database of Outlook PST data file like SysTools Outlook Recovery.
There are free undelete programs that you can download and use if the recycle bin has been emptied. But it also depends on how long ago it was deleted as windows starts to overwrite deleted files. To restore them it should be done as soon as possible
When you delete a file or folder from your computer then it does not permanently deleted from your computer, it goes in recycle bin folder. Recycle bin allows users to browse deleted files, undelete those files that were deleted by mistake, or delete them permanently.
Deleted photoes cannot be recovered on the DSi. Since it does store in a familiar format, you may be able to restore a photo if it was saved to an SD card using an undelete program.
Usually in the trash/deleted items.