Sitecore Workbox Generating Odd Error

Question

I've run into a problem in the Wokbox that seems like a Sitecore bug. When the "Items per Page" drop down is set to anything but "All", I'm able to expand the "Draft" and "Awaiting Approval" lists in the Workflow.

But when the "Items per Page" is set to "All", I get the following error:

Exception in MyWebSite: /sitecore/shell/default.aspx?xmlcontrol=Workbox&mo=preview

Message: Operation is not valid due to the current state of the object. StackTrace: at System.Web.HttpValueCollection.FillFromEncodedBytes(Byte[] bytes, Encoding encoding) at System.Web.HttpRequest.FillInFormCollection()

And at this point, I'm "stuck" - and unable to revert my view back to anything less than "All" in the "Items per Page" drop-down. So, because I cannot revert back, I cannot do anything on the page, and any attempt to expand the Workflow lists (or do anything on the page) generates the above error.

Any thoughts on what is happening and how to fix this?

Answer 1

I followed up on this to keep from leaving this question unanswered. It turns out that this issue was related to another known issue. For the benefit of those who might be getting a similar issue, here's what fixed this:

The problem can occur when Sitecore CMS is installed on systems that have Microsoft security update MS11-100 installed.

Please refer to the similar known issue on SDN:

The Template Builder may fail when saving templates with many fields

The solution: Try to add the following node to the section of the web.config file:

<add key="aspnet:MaxHttpCollectionKeys" value="5000" />