DSFixUI error

Problem signature:
  Problem Event Name:	CLR20r3
  Problem Signature 01:	dsfixgui.exe
  Problem Signature 02:	1.0.0.0
  Problem Signature 03:	50528db1
  Problem Signature 04:	mscorlib
  Problem Signature 05:	4.0.0.0
  Problem Signature 06:	4ee9af8e
  Problem Signature 07:	1204
  Problem Signature 08:	89
  Problem Signature 09:	System.TypeLoadException
  OS Version:	6.1.7601.2.1.0.256.1
  Locale ID:	1033
  Additional Information 1:	0a9e
  Additional Information 2:	0a9e372d3b4ad19135b953a78882e789
  Additional Information 3:	0a9e
  Additional Information 4:	0a9e372d3b4ad19135b953a78882e789