Scans System Drive and Disappears

I am experiencing a bug with Recuva v1.04.104. Recuva works just fine with my other hard drives but if I choose the System Drive it will complete the scan and then suddenly disappear. I have run Recuva in debug mode to get a clue as to whats going on. Here is a selection of the output:

[iNFO ] Recuva v1.04.104[iNFO ] System Info: MS Windows XP SP2, Intel® Pentium® 4 CPU 2.40GHz, 1022MB RAM, NVIDIA GeForce FX 5200[ERROR] Exception: DriveNamesEnumerator.cpp(46) : The device is not ready.[iNFO ] OEM Name NTFS	[iNFO ] Searching for deleted files...[iNFO ] Read from MFT: 259344 records total[ERROR] Exception: NtfsFileRecordImpl.cpp(322) : Invalid MFT record detected[iNFO ] File record is invalid

Another unrelated issue is that when scanning my external hard drive, Recuva will freeze for a minute or two at 99% right before it displays the files.