CRM 2011 - Form errors when opening non customised forms (object doesn't support property or method 'Form load')

You may experience the following error across a number of default entities after installing CRM 2011 on a new server. The errors occur despite having made NO customisations:
There was an error with this field's customized event
Field: window
Event: onload
Error: object doesn't support property or method 'Form load'
Within a fiddler trace, you may see the following:
401 http://<crmserver>/<myorg>/%7B634443390830000000%7D/WebResources/Ribbon_main_system_library.js
404 http://<crmserver>/<myorg>/%7B634443390830000000%7D/WebResources/Ribbon_main_system_library.js
When a Web Resource is requested from the CRM server, a URL is built dynamically. For that, CRM uses a component (that gets installed with CRM) called “Microsoft URL Rewrite 1.1 for IIS 7”, together with a rule that you can see inside the CRM Web site configurations under the URL Rewrite section called “WebResourcesRule”.
It has been seen that in some circumstances the Microsoft URL Rewrite Module does not get loaded properly and/or the rewrite rules are missing. The following can be done to check this:
1)
-Launch IIS Manager on the CRM server
-Select the CRM Website
-Double click Modules under IIS heading
-Verify RewriteModule is listed in the list here and is associated with the following DLL: %SystemRoot%\System32\Inetsrv\rewrite.dll
2)
-Launch IIS Manager on the CRM server
-Select the CRM Website
-Double click URL Rewrite under the IIS heading
-Verify that 3 rules exist here (ClientGlobalContectRule, WebResourcesRule, FederationMetadataRule)
If one or both of the above does not appear correct, then you should perform the following:
A) Make sure that Kernel-mode authentication is enabled:
-Launch IIS Manager on the CRM server
-Select the CRM Website
-Double click Authentication under the IIS heading.
-Select 'Windows Authentication'
-Click on Advanced Settings in the right hand Actions pane.
-Confirm 'Enable Kernel-mode authentication' is marked.
B) Repair or Reinstall the URL RewriteModule:
- The installation msi for the Microsoft URL RewriteModule can be found within the CRM server installation media under a folder called UrlRewriteModule. The file is called rewrite_1.1_amd64_rtw.
- Reboot the CRM Server after reinstalling the module.
When the module is correctly installed, the CRM website web.config file should be automatically updated. To verify this open the CRM website web.config file and make sure the following element is present under <rewrite>.
</security>
<rewrite>
<rules>
<rule name="ClientGlobalContextRule" stopProcessing="true">
<match url="/?([0-9a-zA-Z][^/]*)?/?((?:%7b|\{)[^/]*(?:%7d|\}))?/?(WebResources|Handlers)/ClientGlobalContext.js.aspx" />
<action type="Rewrite" url="/{R:1}/_Common/ClientGlobalContext.js.aspx" />
</rule>
<rule name="WebResourcesRule" stopProcessing="true">
<match url="/?([0-9a-zA-Z][^/]*)?/?((?:%7b|\{)[^/]*(?:%7d|\}))?/?webresources/([^\\?]+)" />
<action type="Rewrite" url="/{R:1}/Handlers/WebResource.ashx?name={R:3}" />
</rule>
<rule name="FederationMetadataRule" stopProcessing="true">
<match url="FederationMetadata/2007-06/FederationMetadata.xml" />
<action type="Rewrite" url="/Handlers/FederationMetadata.ashx" />
</rule>
</rules>
</rewrite>
</system.webServer>

Microsoft URL Rewrite Module 1.1 for IIS 7 (x64) can be downloaded from below:
http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=16784

Best Regards
Mubasher Sharif