I wanted to block realplay.exe from adding an autorun entry in the registry HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run.
I added the key by choosing it from the registry tree offered in
D+>Advanced>Computer Security Policy>[%program files%\real\realplay.exe]>Access Rights>Protected Registry Keys (Allow)>Modify>Blocked Registry Keys>Add>Registry Entries>[here I dragged the respective registry key from Existing items to Selected items]
D+ added the entry HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run*
This does not protect the autorun entries!
I manually changed the entry to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run* (added a back slash before the asterisk)
Now the autorun entries are being blocked.