I am helping a friend import several thousand old photos into LR CC 2015. Some of the PSD files generate the error "The files use an unsupported color mode.". What must we do to be able to import these PSD files? Thanks.
Find the files, and see if they are duotone mode - that's a color mode that Lightroom can't handle. Converting them to RGB mode in Photoshop will get around this and allow you to import the files, but it may not be what your friend wants to do.
Thanks John. I'll try that.