I am not sure if there is any solution. I have followed all the advices, deleted OOBE folder, deleted the shared folder, used Adobe CC Cleaner to clean everything, installed Creative Cloud again and it worked! It synchronized the folder successfully. And in few hours, it was broken again. Adobe really needs to fix that and find the source of the problem. Why to use this cloud solution when it is not capable of the primary function it should do? Obviously there are many people who have similar problems with that. My computer is obviously capable to synchronize properly. But why is it so that it works only few hours after complete reinstall? This week W10 machine does not work and W7 machine does not have problems. Few weeks ago W7 machine was not working but the W10 was. Quite unreliable solution.
I'm having the same problem, I've tried what you said and also tried to uninstall everything, it took 10 hours to reinstall and synch all my files, it seemed fine until this morning and now it has problem again.