Operation is not valid due to the current state of the object error during postback

Question

I had an aspx page which was working well  but suddenly I am getting the error  Operation is not valid due to the current state of the object   whenever a postback is done   The stack trace is      at   System Web HttpValueCollection ThrowIfMaxHttpCollectionKeysExceeded     at System Web HttpValueCollection FillFromEncodedBytes Byte   bytes    Encoding encoding  at System Web HttpRequest FillInFormCollection     Can someone help

User · Answer

If your stack trace looks like following then you are sending a huge load of json objects to server

Operation is not valid due to the current state of the object. 
    at System.Web.Script.Serialization.JavaScriptObjectDeserializer.DeserializeDictionary(Int32 depth)
    at System.Web.Script.Serialization.JavaScriptObjectDeserializer.DeserializeInternal(Int32 depth)
    at System.Web.Script.Serialization.JavaScriptObjectDeserializer.BasicDeserialize(String input, Int32 depthLimit, JavaScriptSerializer serializer)
    at System.Web.Script.Serialization.JavaScriptSerializer.Deserialize(JavaScriptSerializer serializer, String input, Type type, Int32 depthLimit)
    at System.Web.Script.Serialization.JavaScriptSerializer.DeserializeObject(String input)
    at Failing.Page_Load(Object sender, EventArgs e) 
    at System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e)
    at System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e)
    at System.Web.UI.Control.OnLoad(EventArgs e)
    at System.Web.UI.Control.LoadRecursive()
    at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

For resolution, please update your web config with following key. If you are not able to get the stack trace then please use fiddler. If it still does not help then please try increasing the number to 10000 or something

<configuration>
<appSettings>
<add key="aspnet:MaxJsonDeserializerMembers" value="1000" />
</appSettings>
</configuration>

For more details, please read this Microsoft kb article

User · Answer

I didn t apply paging on my gridview and it extends to more than 600 records  with checkbox  buttons  etc   and the value of 2001 didn t work  You may increase the value  say 10000 and test    lt appSettings gt   lt add key  aspnet MaxHttpCollectionKeys  value  10000    gt   lt  appSettings gt

User · Answer

Somebody posted quite a few form fields to your page   The new default max introduced by the recent security update is 1000   Try adding the following setting in your web config s  lt appsettings gt  block  in this block you are maximizing the MaxHttpCollection values this will override the defaults set by  net Framework  you can change the value accordingly as per your form needs   lt appSettings gt       lt add key  aspnet MaxHttpCollectionKeys  value  2001    gt    lt  appSettings gt    For more information please read this post  For more insight into the security patch by microsoft you can read this Knowledge base article

User · Answer

For ASP NET 1 1  this is still due to someone posting more than 1000 form fields  but the setting must be changed in the registry rather than a config file  It should be added as a DWORD named MaxHttpCollectionKeys in the registry under   HKEY LOCAL MACHINE SOFTWARE Microsoft ASP NET 1 1 4322 0   for 32-bit editions of Windows  and  HKEY LOCAL MACHINE SOFTWARE Wow6432Node Microsoft ASP NET 1 1 4322 0   for 64-bit editions of Windows

[asp.net] 'Operation is not valid due to the current state of the object' error during postback

Examples related to asp.net