Attachedment in Saved eMail File corrupted

When received a forwarded email (forward as attachment along with other files like .doc, .xls, .jpg etc attached to the email), I used to be able to split out the original email by click on the attachment line at the bottom, then select the .eml and save it. All attachments to that email will be saved together properly. Then, I can File->Open->Saved Message to open the file. I can then right click on the message body and chose Copy to save the entire email along with attachments to a email folder. After recent update, when I try to open the files attached to the email after the above split and save action, the files attached to the original email are corrupted. I tried to save the file out from the above splitted out email but the file saved is only 1 bite. Is this a bug ? Is there someway of splitting out a forwarded email and save it back into the IN folder easily ?