upgraded Nikon D700 to D750 and can't upload images; do I need to upgrade LTRM 4 and PHSHP CS6 to upload?
If you mean opening NEFs from your new Nikon, you need Adobe Camera Raw 8.7
Go to Help > Updates on CS6 to download and install it.
I don't know anything about LR4, so you should check the LR forums.
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