AppCrash message on startup

Every time Vista starts up, I get a message saying that windows stopped
working (or something like that). The details are below. Anyone have an
idea what this is? I've searched through the registry and looked in the
startup folder and services, but can't find anything. What is fsquirt.exe?

Problem signature:
Problem Event Name: APPCRASH
Application Name: fsquirt.exe
Application Version: 5.1.2600.2180
Application Timestamp: 41107dd7
Fault Module Name: USERENV.dll
Fault Module Version: 5.1.2600.2180
Fault Module Timestamp: 411096b9
Exception Code: c0000005
Exception Offset: 0009022f
OS Version: 6.0.6000.2.0.0.256.1
Locale ID: 1033
Additional Information 1: 13d7
Additional Information 2: 5c42fa051d90c20eb6ae78966db2c984
Additional Information 3: 1621
Additional Information 4: 60daf5f1556a4da837fb99da9bf0ae19