I just installed windows update KB2984006 and, since then, everytime windows starts, I get error "Changelcon MFC Application has stopped working"

Yesterday, I installed the following optional update:

Update for Windows 8.1 for x64-based Systems (KB2984006)

Installation date: ‎25/‎09/‎2014 09:36 a.m.
Installation status: Succeeded
Update type: Optional

More information:
http://support.microsoft.com/kb/2984006

Since then, every time I turn on my pc I get this error:

Changelcon MFC Application has stopped working

Problem signature:
Problem Event Name: APPCRASH
Application Name: UMonit64.exe
Application Version: 13.0.0.0
Application Timestamp: 52007056
Fault Module Name: ustor.dll
Fault Module Version: 6.3.9600.17278
Fault Module Timestamp: 53eeb4a3
Exception Code: c0000135
Exception Offset: 00098f05
OS Version: 6.3.9600.2.0.0.768.101
Locale ID: 11274
Additional Information 1: 1abe
Additional Information 2: 1abee00edb3fc1158f9ad6f44f0f6be8
Additional Information 3: 1abe
Additional Information 4: 1abee00edb3fc1158f9ad6f44f0f6be8

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Any suggestion on how to solve this? thanks.