Take these steps if the cursor changes from an arrow to a white "prohibited" symbol when you try to move an icon on the Desktop.
Sometimes the problem may be solved just by logging out or rebooting. Try that first, if you haven't already done it. Otherwise, continue.
Select the icon of your home folder (a house) in the sidebar of a Finder window and open it. The Desktop folder is one of the subfolders. Select it and open the Info window. In the General section of the window, the Kind will be either Folder or something else, such as Anything.
If the Kind is Folder, uncheck the box marked Locked. Close the Info window and test.
If the Kind is not Folder, make sure the Locked box is not checked and that you have Read & Write privileges in the Sharing & Permissions section. Then close the Info window and do as follows.
Back up all data.
Triple-click anywhere in the line below on this page to select it:
xattr -d com.apple.FinderInfo Desktop
Copy the selected text to the Clipboard by pressing the key combination command-C.
Launch the Terminal application in any of the following ways:
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ Open LaunchPad. Click Utilities, then Terminal in the icon grid.
Paste into the Terminal window (command-V). You should get a new line ending in a dollar sign (“$”). Quit Terminal.
If the problem is now resolved, and if you use iPhoto, continue.
Quit iPhoto if it's running. Launch it while holding down the option key. It will prompt you to select a library. Choose the one you want to use (not the Desktop folder.)
