When sending Excel sheets using the menu item "File" -> "Sent To" -> "Mail recipient (as attachment)" I get additional copies of the email in the Inbox.

When I press "send" then I get 2 copies of the email in Outlook - as expected one in the Outbox (which moves into the Sent folder as soon it is sent off) and an additional one in the Inbox.

How do I stop the copy message appearing in the Inbox?

System: Excel 2000, Outlook 2000, Windows XP. Antivirus is AVG Free 2011.

I know this is a very old system, but it is not my PC and there isn't any chance to get it replaced in the near future yet.

SOme further details: The copy in the inbox appears at the same time as the normal copy goes into the Outbox (i.e. as soon I press send). It doesn't contain anything in the From field (i.e. there is no sender, just the recipient of the mail). It has a different icon in Outlook to the other emails - the icon is the one for "saved or unsent message".

I tried it with a few different spreadsheets and it happens with all of them. It happens with every recipient, and it only happens if sending from within Excel (i.e. using the Send to menu item). I can delete the attachment before sending and it will still create a copy. If I create a new message in Outlook and then add the Excel document as attachment then I don't get the copy of the message in the inbox, it only happens when using the send to item in Excel.

It only started doing this recently. Around that time the Antivirus (AVG Free) was upgraded to the latest version (from the previous version - 2010? - to version 2011), but this might not be related.

I thought I know Excel really well but have never seen this happening before, and I can't find any setting in Excel or Outlook that is causing this.

Any ideas?