This is and old question, but all the answers I managed to find in the Internet didn't solved my issue.
I am using a Logitech wireless keyboard on my iPad --- "Logitech Ultrathin Keyboard Cover" to be more precise.
I use Parallels on my iPad to access my Windows 7 computer.
When I go into it, I am asked to press Ctrl+Alt+Del to start a session. I am not allowed to disable that option on my Windows computer.
I have tried all the keyboard combinations, but nothing seems to work. How can I press Ctrl+Alt+Del on my wireless keyboard???
Fn
+Backspace
=Del
. Have you tried that?