When viewing a list of attachments, a new version of an existing attachment can be added simply by uploading an attachment with the same filename on the attachment view. Click the blue arrow next to an attachment to display previous versions of the attachment.
Existing files will be kept with the name 'Version x', where the value of 'x' increments with each upload of an attachment with the same filename.
Screenshot: Attachment versions
Some additional notes:
<confluence_home>/attachments directory. (See Attachment Storage Configuration in the Administrator's Guide.) There is no limit to the number of attachments/versions, provided that there is enough disk space.Attaching Files to a Page
Moving an Attachment
Viewing Attachment Details
Working with Attachments
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