So I just made the switch from iPhoto to Photos and I would like to upload all my pics to iCloud. I had moved my iPhoto folder to an external drive long ago as my photo library is huge. Now when I try to upload my pics to iCloud from Photos I get an error message stating "iCloud can only be used with the System Photo Library" which is empty on my Mac hard drive. Is there any way to make the folder on my external the System Photo Library? Maybe point the Photos app to it or rename the folder on my external drive to System Photo Library? I searched the web and came up with nothing at all. I know you guys will know whether this can be done or not, if not I will be shocked. Thanks in advance guys, this is driving me nuts.