Updated Version Downloaded But Will Not Open

I finished a new photobook and was ready to upload and buy it. When I went back to my laptop to reopen and continue with the upload and payment a message appeared saying I had to download the newer version of Vistaprint. How ever when I tried to open the photobook offline editing a message came up to check my firewall settings for 'apc.exe'. This I did and my firewall has been given permission to allow. Have had no trouble with previous photobooks only since the newer version was uploaded have I had this problem.