Explorer keeps crashing throughout the day.

Hi there, 

Win Explorer is continually crashing throughout the day (10x). Not sure what could be causing it and wanted to see if anyone had any thoughts? The closest thing I can think of is when I recently installed Tortoise SVN.

Faulting application name: explorer.exe, version: 6.1.7601.17567, time stamp: 0x4d6727a7
Faulting module name: ntdll.dll, version: 6.1.7601.17725, time stamp: 0x4ec49b60
Exception code: 0xc000071f
Fault offset: 0x00099bc2
Faulting process id: 0x%9
Faulting application start time: 0x%10
Faulting application path: %11
Faulting module path: %12