Exchange 2007 OWA error Outlook Web Access did not initialize

I have started receiving the following error when trying to access OWA on an Exchange 2007 server, running on Windows Server Standard 2008:

Web page error

Outlook Web Access did not initialize. An event has been logged so that the system administrator can resolve the issue. Please contact technical support
for your organization.

No more threads can be created in the system. (Exception from HRESULT: 0x800700A4)

Error details

Request
Url: https://mail.domain_name.org:443/owa/auth/error.aspx?aspxerrorpath=/owa/auth/logon.aspx
User host address: 68.xxx.xxx.xxx

Exception
Exception type: System.Runtime.InteropServices.COMException
Exception message: No more threads can be created in the system. (Exception from HRESULT: 0x800700A4)

Call stack

System.Runtime.InteropServices.Marshal.ThrowExceptionForHRInternal(Int32 errorCode, IntPtr errorInfo)
System.Management.ManagementEventWatcher.Start()
Microsoft.Exchange.Clients.Owa.Core.OwaRegistryKeys.RegisterSMIMERegistryChangeEvent()
Microsoft.Exchange.Clients.Owa.Core.OwaRegistryKeys.Initialize()
Microsoft.Exchange.Clients.Owa.Core.Globals.InitializeApplication()
Microsoft.Exchange.Clients.Owa.Core.Global.ExecuteApplicationStart(Object sender, EventArgs e)

Event log error on server,

Log Name:      Application
Source:        ASP.NET 2.0.50727.0
Date:          2/3/2009 5:51:17 AM
Event ID:      1309
Task Category: Web Event
Level:         Warning
Keywords:      Classic
User:          N/A
Computer:      BFCSSVR01.domain_name.local
Description:
Event code: 3005
Event message: An unhandled exception has occurred.
Event time: 2/3/2009 5:51:17 AM
Event time
(UTC): 2/3/2009 12:51:17 PM
Event ID: 5443d9ed1b3748109e111c81b5293358
Event sequence: 2
Event occurrence: 1
Event detail code: 0
 
Application information:
   
Application domain: /LM/W3SVC/1/ROOT/owa-9-128781390694645366
    Trust level: Full
    Application Virtual Path: /owa
   
Application Path: D:\Program Files\Microsoft\Exchange Server\ClientAccess\owa\
   
Machine name: BFCSSVR01
 
Process information:
    Process ID: 2292
    Process name: w3wp.exe
    Account name: NT AUTHORITY\SYSTEM
 
Exception information:
   
Exception type: COMException
    Exception message: No more threads can be created in the system. (Exception from HRESULT: 0x800700A4)
 
Request information:
   
Request URL: https://mail.bfcsfamily.org:443/owa/auth/logon.aspx?replaceCurrent=1&url=https2/3/2009 5:51:17 AMaAn unhandled exception has occurred.fAn unhandled
exception has occurred.fmail.bfcsfamily.orgAn unhandled exception has occurred.fowa
    Request path: /owa/auth/logon.aspx
    User host address: 68.xxx.xxx.xxx
   
User:  
    Is authenticated: False
    Authentication Type:  
    Thread account name: NT AUTHORITY\SYSTEM
 
Thread information:
    Thread ID: 10
   
Thread account name: NT AUTHORITY\SYSTEM
    Is impersonating: False
    Stack trace:    at System.Runtime.InteropServices.Marshal.ThrowExceptionForHRInternal(Int32 errorCode,
IntPtr errorInfo)
   at System.Management.ManagementEventWatcher.Start()
   at Microsoft.Exchange.Clients.Owa.Core.OwaRegistryKeys.RegisterSMIMERegistryChangeEvent()
   at Microsoft.Exchange.Clients.Owa.Core.OwaRegistryKeys.Initialize()
   at Microsoft.Exchange.Clients.Owa.Core.Globals.InitializeApplication()
   at Microsoft.Exchange.Clients.Owa.Core.Global.ExecuteApplicationStart(Object sender, EventArgs e)
 
 
Custom event details:

Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <System>
    <Provider Name="ASP.NET 2.0.50727.0" />
    <EventID Qualifiers="32768">1309</EventID>
    <Level>3</Level>
    <Task>3</Task>
    <Keywords>0x80000000000000</Keywords>
    <TimeCreated SystemTime="2009-02-03T12:51:17.000Z" />
    <EventRecordID>35019</EventRecordID>
    <Channel>Application</Channel>
    <Computer>BFCSSVR01.domain_name.local</Computer>
    <Security />
  </System>
  <EventData>
    <Data>3005</Data>
    <Data>An unhandled exception has occurred.</Data>
    <Data>2/3/2009 5:51:17 AM</Data>
    <Data>2/3/2009 12:51:17 PM</Data>
    <Data>5443d9ed1b3748109e111c81b5293358</Data>
    <Data>2</Data>
    <Data>1</Data>
    <Data>0</Data>
    <Data>/LM/W3SVC/1/ROOT/owa-9-128781390694645366</Data>
    <Data>Full</Data>
    <Data>/owa</Data>
    <Data>D:\Program Files\Microsoft\Exchange Server\ClientAccess\owa\</Data>
    <Data>BFCSSVR01</Data>
    <Data>
    </Data>
    <Data>2292</Data>
    <Data>w3wp.exe</Data>
    <Data>NT AUTHORITY\SYSTEM</Data>
    <Data>COMException</Data>
    <Data>No more threads can be created in the system. (Exception from HRESULT: 0x800700A4)</Data>
    <Data>https://mail.domain_name.org:443/owa/auth/logon.aspx?replaceCurrent=1&amp;url=https%3a%2f%2fmail.domain_name.org%2fowa</Data>
    <Data>/owa/auth/logon.aspx</Data>
    <Data>68.107.222.172</Data>
    <Data>
    </Data>
    <Data>False</Data>
    <Data>
    </Data>
    <Data>NT AUTHORITY\SYSTEM</Data>
    <Data>10</Data>
    <Data>NT AUTHORITY\SYSTEM</Data>
    <Data>False</Data>
    <Data>   at System.Runtime.InteropServices.Marshal.ThrowExceptionForHRInternal(Int32 errorCode, IntPtr errorInfo)
   at System.Management.ManagementEventWatcher.Start()
   at Microsoft.Exchange.Clients.Owa.Core.OwaRegistryKeys.RegisterSMIMERegistryChangeEvent()
   at Microsoft.Exchange.Clients.Owa.Core.OwaRegistryKeys.Initialize()
   at Microsoft.Exchange.Clients.Owa.Core.Globals.InitializeApplication()
   at Microsoft.Exchange.Clients.Owa.Core.Global.ExecuteApplicationStart(Object sender, EventArgs e)
</Data>
  </EventData>
</Event>