I've come across a bunch of NZB's that download and appear to be un-raring but do not extract anything.  They don't show up in failed and they don't show up on the files list.  They just vanish.
I've sent a example to ts@newsbin.com with a reference to this post if you want to take a look.  Maybe it's a new obfuscation issue or something.  This started happening about a week ago.
NZBGet extracts these with no problem.  There are no odd file types inside.
I'm using: 6.90 5524
			
		




