Internet Explorer 7 and 8 freeze loading MVC3 Application

Question

I'm having an intermittent issue with Internet Explorer 8 and 7 . I've been testing with both for few days now. My guess is that it's related to JavaScript .

After a random number of page views/refreshes within my MVC 3 application, I get one of the following:

1. A blank white screen

2. The previously rendered page, without any ability to interact with the page (sometimes including scrolling)

I've tried commenting out all of my JavaScript , without any change in results. I've tried deploying to different servers without any results. I've tried different clients without any results. I've tried to search logs on the client and server without any results. Internet Explorer 9 , Chrome and Firefox appear unaffected. The application will be used primarily with Internet Explorer 7 and 8 .

I would appreciate any and all suggestions as to what to try next.

Javascript libraries in the project:

jquery-1.5.1-vsdoc.js
jquery-1.5.1.js
jquery-1.5.1.min.js
jquery-ui-1.8.11.js
jquery-ui-1.8.11.min.js
jquery-ui-1.8.20.custom.min.js
jquery.min.js
jquery.unobtrusive-ajax.js
jquery.unobtrusive-ajax.min.js
jquery.validate-vsdoc.js
jquery.validate.js
jquery.validate.min.js
jquery.validate.unobtrusive.js
jquery.validate.unobtrusive.min.js
MicrosoftAjax.debug.js
MicrosoftAjax.js
MicrosoftMvcAjax.debug.js
MicrosoftMvcAjax.js
MicrosoftMvcValidation.debug.js
MicrosoftMvcValidation.js
modernizr-1.7.js
modernizr-1.7.min.js
pngfix.js

Answer 1

Removal of the following appears to have fixed the issue:

<!--[if lte IE 7.]>
    <script type="text/javascript" src="@Url.Content("~/Scripts/pngfix.js")"></script>
<![endif]-->    

<!--[if (gte IE 6)&(lte IE 8)]>
    <script type="text/javascript" src="@Url.Content("~/Scripts/IE9_fix.js")"></script>
<![endif]--> 

<!--[if lt IE 9.]>
    <script src="@Url.Content("~/Scripts/html5.js")" type="text/javascript"></script>
<![endif]-->