How to delete all files and folders in a folder by cmd call

del c:\destination\*.* /s /q worked for me. I hope that works for you as well.

I think the easiest way to do it is:

rmdir /s /q "C:\FolderToNotToDelete\"

The last "\" in the path is the important part.

No, I don't know one.

If you want to retain the original directory for some reason (ACLs, &c.), and instead really want to empty it, then you can do the following:

del /q destination\*
for /d %x in (destination\*) do @rd /s /q "%x"

This first removes all files from the directory, and then recursively removes all nested directories, but overall keeping the top-level directory as it is (except for its contents).

Note that within a batch file you need to double the % within the for loop:

del /q destination\*
for /d %%x in (destination\*) do @rd /s /q "%%x"