windows 7 ultimate explorer crushes

Hello

i have a problem with my explorer, it crashes every 5 minutes after i login to my account
all i can get is this from the event viewer.

please and thanks for your help

Log Name:      Application
Source:        Application Error
Date:          9/25/2011 11:15:35 PM
Event ID:      1000
Task Category: (100)
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      Dillon-PC
Description:
Faulting application name: Explorer.EXE, version: 6.1.7600.16450, time stamp: 0x4aebab8d
Faulting module name: msvcrt.dll, version: 7.0.7600.16385, time stamp: 0x4a5bdfbe
Exception code: 0xc00000fd
Fault offset: 0x0000000000002c90
Faulting process id: 0xa88
Faulting application start time: 0x01cc7c0fccda4692
Faulting application path: C:\Windows\Explorer.EXE
Faulting module path: C:\Windows\system32\msvcrt.dll
Report Id: f1f4329e-e806-11e0-abc9-6cf049e73869
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <System>
    <Provider Name="Application Error" />
    <EventID Qualifiers="0">1000</EventID>
    <Level>2</Level>
    <Task>100</Task>
    <Keywords>0x80000000000000</Keywords>
    <TimeCreated SystemTime="2011-09-26T06:15:35.000000000Z" />
    <EventRecordID>27137</EventRecordID>
    <Channel>Application</Channel>
    <Computer>Dillon-PC</Computer>
    <Security />
  </System>
  <EventData>
    <Data>Explorer.EXE</Data>
    <Data>6.1.7600.16450</Data>
    <Data>4aebab8d</Data>
    <Data>msvcrt.dll</Data>
    <Data>7.0.7600.16385</Data>
    <Data>4a5bdfbe</Data>
    <Data>c00000fd</Data>
    <Data>0000000000002c90</Data>
    <Data>a88</Data>
    <Data>01cc7c0fccda4692</Data>
    <Data>C:\Windows\Explorer.EXE</Data>
    <Data>C:\Windows\system32\msvcrt.dll</Data>
    <Data>f1f4329e-e806-11e0-abc9-6cf049e73869</Data>
  </EventData>
</Event>