SaaS CMS has officially launched! Learn more now.

Per Nilsson
Jan 18, 2012
(4 votes)

MS Update MS11-100 breaks sites with more than 1000 parameters

Got a ticket to the support with an error I haven't seen before and found out that the reason is a two weeks old Microsoft hotfix. It might happen to someone else so wanted to write a few rows how to solve it if you run into the problem.

During the holidays MS published the security update MS11-100. This update has been released to fix ASP.NET DoS vulnerability and limits the amount of parameters for a single HTTP POST to 1000. It's probably not that often you use more than 1000 parameters but this is the error you will end up with if you do (the one to look for is ThrowIfMaxHttpCollectionKeysExceeded):


Operation is not valid due to the current state of the object.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:
[InvalidOperationException: Operation is not valid due to the current state of the object.]
System.Web.HttpValueCollection.ThrowIfMaxHttpCollectionKeysExceeded() +2692302
System.Web.HttpValueCollection.FillFromEncodedBytes(Byte[] bytes, Encoding encoding) +61
System.Web.HttpRequest.FillInFormCollection() +148

[HttpException (0x80004005): The URL-encoded form data is not valid.]
System.Web.HttpRequest.FillInFormCollection() +206
System.Web.HttpRequest.get_Form() +68
System.Web.HttpRequest.get_HasForm() +8735447
System.Web.UI.Page.GetCollectionBasedOnMethod(Boolean dontReturnNull) +97
System.Web.UI.Page.DeterminePostBackMode() +63
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +133


When they added the limitation of parameters they also added the possiblilty to override the default value by a new setting in web.config. Can also mention that it’s not possible to apply different values at different locations. 

Add the following setting to web.config with a value larger than 1000 (default):

   <add key="aspnet:MaxHttpCollectionKeys" value="some number here"/>

The above setting should fix the problem.


Info about the hotfix and people getting the error in the discussion following the article:

The same error discussed in a forum

Jan 18, 2012


Please login to comment.
Latest blogs
Optimizely Graph – Faceting with Geta Categories

Overview As Optimizely Graph (and Content Cloud SaaS) makes its global debut, it is known that there are going to be some bugs and quirks. One of t...

Eric Markson | Jul 22, 2024 | Syndicated blog

Integration Bynder (DAM) with Optimizely

Bynder is a comprehensive digital asset management (DAM) platform that enables businesses to efficiently manage, store, organize, and share their...

Sanjay Kumar | Jul 22, 2024

Frontend Hosting for SaaS CMS Solutions

Introduction Now that CMS SaaS Core has gone into general availability, it is a good time to start discussing where to host the head. SaaS Core is...

Minesh Shah (Netcel) | Jul 20, 2024

Optimizely London Dev Meetup 11th July 2024

On 11th July 2024 in London Niteco and Netcel along with Optimizely ran the London Developer meetup. There was an great agenda of talks that we put...

Scott Reed | Jul 19, 2024