Webserver crash when site runs on IIS 7.5

Hi

When we run a page in our website there is a crash on the server with a message;

An unhandled Microsoft .Net Framework exception occurred in w3wp.exe [2576]

Some relevant events from Application Log are below. What could be the problem?

Thanks

Regards

Log Name:      Application
Source:        Application Error
Date:          22/08/2012 17:43:34
Event ID:      1000
Task Category: (100)
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      myserver
Description:
Faulting application name: w3wp.exe, version: 7.5.7601.17514, time stamp: 0x4ce7afa2
Faulting module name: MSVCR100_CLR0400.dll, version: 10.0.30319.1, time stamp: 0x4ba2211c
Exception code: 0xc00000fd
Fault offset: 0x0000000000057f91
Faulting process id: 0x15c4
Faulting application start time: 0x01cd80852d543ba8
Faulting application path: c:\windows\system32\inetsrv\w3wp.exe
Faulting module path: C:\Windows\system32\MSVCR100_CLR0400.dll
Report Id: 830548ec-ec78-11e1-9fca-00215aeddd4a

Log Name:      Application
Source:        Application Error
Date:          22/08/2012 17:44:44
Event ID:      1000
Task Category: (100)
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      myserver
Description:
Faulting application name: w3wp.exe, version: 7.5.7601.17514, time stamp: 0x4ce7afa2
Faulting module name: clr.dll, version: 4.0.30319.269, time stamp: 0x4ee9d6e1
Exception code: 0xc00000fd
Fault offset: 0x00000000000320bc
Faulting process id: 0xa10
Faulting application start time: 0x01cd808566649899
Faulting application path: c:\windows\system32\inetsrv\w3wp.exe
Faulting module path: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\clr.dll
Report Id: ac802392-ec78-11e1-9fca-00215aeddd4a
Event Xml:

Log Name:      Application
Source:        Application Error
Date:          23/08/2012 13:20:23
Event ID:      1000
Task Category: (100)
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      myserver
Description:
Faulting application name: w3wp.exe, version: 7.5.7601.17514, time stamp: 0x4ce7afa2
Faulting module name: ntdll.dll, version: 6.1.7601.17725, time stamp: 0x4ec4aa8e
Exception code: 0xc00000fd
Fault offset: 0x0000000000053560
Faulting process id: 0x1458
Faulting application start time: 0x01cd81298e90f0e0
Faulting application path: c:\windows\system32\inetsrv\w3wp.exe
Faulting module path: C:\Windows\SYSTEM32\ntdll.dll
Report Id: e942a277-ed1c-11e1-9fca-00215aeddd4a