Well this has happened to me once (right now). Steps to reproduce:
1. Make a folder called "!Shared" on your Documents (can be any name anyways)
2. Share it
3. Make a new folder inside your Documents called "2" (for example, can be any name)
4. Paste a bunch of files in the newly created folder.
5. Try to create a new folder in your Documents and change its name.
You'll see you can't rename the folder while it is copying files to "2" because the window is constantly doing a refresh. I dunno why, I assume it is because it is monitoring the files that are being copied to the folder within :/
I also think this is related to this bug:
Stop the constant refresh in the folder where there is no file activity? it's just silly to do code-wise and annoying for the user. I had to wait until the copy was finished so I could rename my newly-created folder.