Move an attachment from one page to another
To move an attachment to a different page, click on More Actions, select Manage Site.
From the menu on the left, select Attachments.
From this screen, you can manage any attachment including moving an attachment to another page.
The problem is that if you have a site that has many hundreds of attachments there is currently no easy way of filtering to the attachment you wish to manage. However, the attachments are listed in last updated order and we can take advantage of this.
Go to the page with the attachment you wish to move and make a small amendment to the name of the attachment (click on the attachment name) e.g. add a space to the end of the name (or delete a space). Now go to the Attachment page. The attachment you have just edited will now be at the top of the list. Check the box next to the attachment and select Move from the menu at the top.
Fortunately, the move dialogue allows you to select the page to move the attachment to in several ways: by searching for the page, by using the site map or by selecting from a list of recently changed pages.
Select the page to move the attachment to by whichever means suits you best.