Sorry, believe I may have been confused by what were you saying. Is this in the automatic upgrade process? Have you tried to upload manually the files?
To do a manual upgrade, you would do this by downloading a full set of files in the Client Area and exacting them to your computer. Once done, upload the contents of the "ips_*****" folders to your server, overwriting what is there. When all files have successfully uploaded, you will want to go to /admin/upgrade to complete the upgrade.