Make Windows always copy files when dragging and dropping them

Is there a way to change the default drag and drop behavior in Windows 7?

As of now it seems that if the location is on the same drive it'll move onto the other, otherwise if they are in different drives it'll copy.

Is there a way to change the setting so it'll always copy it?

You could try the solution suggested in this answer: https://superuser.com/a/248961/71432

Alternatively, if you're not into coding, you can alter the behavior of drag-and-drop by manually holding down one of the modifier keys while dropping:

• Hold down the Control key to always copy.
• Hold down the Shift key to always move.
• Hold down the Alt key to always make a shortcut.

If you have trouble or do not like remembering the key combinations Amazed suggested to use, then drag and drop with the right mouse button and you will be presented a nice window with these same options: copy, move, shortcut and cancel.

There is a RegKey for this:

HKEY_CLASSES_ROOT\AllFileSystemObject\DefaultDropEffect

Keep in mind that although all other keys in AllFilesystemObjects are REG_SZ this one has to be a DWORD. The value for "always copy" would be 1 for "always move" it would be 2, and "create shortcut" 4. In this case decimal or hexadecimal does not make a difference as it is the same anyways.

The change will take effect without reboot, so you can immediately test it.

There is also a tool that does this called "Drag'n'Drop Editor" whichs features later were taken over to WinAero Tweaker.