You can delete documents you posted or documents on your profile wall.
If you are a service administrator, you can delete any document.
If a document has multiple versions, delete removes only the selected version.
Deleting a document or document version deletes it for all members of the Conversation or wall.
There's no undelete, so be sure about deleting the file before you act.
If you don't see the Delete option when working with a document on someone's wall, the person doesn't allow other people to post to (or change) his or her wall.
While viewing a list of documents, tap under the document, then tap Delete.
Alternately, you can delete the document while viewing it: