How do I delete a directory tree that isn't empty?

You can't use RemoveDirectory, because it only works on empty directories/folders. But you CAN use a Shell function for this, the ubiquitous SHFileOperation :

SHFILEOPSTRUCT sh;

sh.hwnd = GetSafeHwnd();
sh.wFunc = FO_DELETE;
sh.pFrom = "c:\\test\0";
sh.pTo = NULL;
sh.fFlags = FOF_NOCONFIRMATION | FOF_SILENT;
sh.hNameMappings = 0;
sh.lpszProgressTitle = NULL;

SHFileOperation (&sh);

That code will softly and silently remove an entire tree, starting from (and including) c:\test.

NOTE : under NT, this may fail because a process has a folder or subfolder as its current directory. This problem does not arise in Win9x.

~ Extra Wrinkle ~

This comes courtesy of Ed Eichman, who wrote to tell me about a problem he had with removing a folder tree:

I had a "remove dir" function that removed all files in the dir, and then deleted the dir itself. I used CFileFind to get and delete the files, and then called _rmdir WITHOUT FIRST CALLING CFileFind.Close ()!
Adding the Close fixed my problem.

Author : Bob Moore