Can any one help with this error.

I am Automating Outlook to move E-mails from a public sub folder to another sub folder, after I have extracted the Attachment files. This eror is coming up after I issue the Item.Move(MoveToFolder), the Item is copied to the MoveTofolder, but I think its trying to Delete the original. Is it keeping the file open, and it thinks some one is still using it, if so, how do I release the item so it can be deleted, or am I barking up the wrong tree

thanks in advance
iain