Hi I've also been having an issue with copy and paste, and drag and drop.
I've spent about 5 hours researching and trying all the fixes microsoft has suggested on these forums to no avail.
Low and behold I solved my problem. I was going to the DUMB@$$ APS thing to get to my pictures and my external hard drive and apparently you cannot copy and paste or drag and drop from the APS to your desktop or external drive! I know probably too simple for any forum experts, and isn't the issue that some have, but you might want to let people know about this FIRST!
Just use file manager, forget about using the APS. What are these for anyhow? Just make things confusing.