Validation of viewstate MAC failed.

Question

4.60/5 (3 votes)

See more:

Following error occurred when I am clicking on button on page. I hope it occurred when a request raised after session expired. Please give proper solution...

Server Error in '/' Application.

HTML

Validation of viewstate MAC failed. If this application is hosted by a Web Farm or cluster, ensure that <machineKey> configuration specifies the same validationKey and validation algorithm. AutoGenerate cannot be used in a cluster.

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.

Exception Details: System.Web.HttpException: Validation of viewstate MAC failed. If this application is hosted by a Web Farm or cluster, ensure that <machinekey> configuration specifies the same validationKey and validation algorithm. AutoGenerate cannot be used in a cluster.

Source Error:

[No relevant source lines]


Source File: c:\windows\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files\root\e529ecf2\18fea36a\App_Web_q6lqkkxv.13.cs    Line: 0

Stack Trace:

[ViewStateException: Invalid viewstate. 
	Client IP: 182.71.144.134
	Port: 2418
	User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:12.0) Gecko/20100101 Firefox/12.0
	ViewState: 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...]

[HttpException (0x80004005): Validation of viewstate MAC failed. If this application is hosted by a Web Farm or cluster, ensure that <machinekey> configuration specifies the same validationKey and validation algorithm. AutoGenerate cannot be used in a cluster.]
   System.Web.UI.ViewStateException.ThrowError(Exception inner, String persistedState, String errorPageMessage, Boolean macValidationError) +106
   System.Web.UI.ViewStateException.ThrowMacValidationError(Exception inner, String persistedState) +14
   System.Web.UI.ObjectStateFormatter.Deserialize(String inputString) +237
   System.Web.UI.ObjectStateFormatter.System.Web.UI.IStateFormatter.Deserialize(String serializedState) +4
   System.Web.UI.Util.DeserializeWithAssert(IStateFormatter formatter, String serializedState) +37
   System.Web.UI.HiddenFieldPageStatePersister.Load() +207
   System.Web.UI.Page.LoadPageStateFromPersistenceMedium() +105
   System.Web.UI.Page.LoadAllState() +43
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +6785
   System.Web.UI.Page.ProcessRequest(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +242
   System.Web.UI.Page.ProcessRequest() +80
   System.Web.UI.Page.ProcessRequestWithNoAssert(HttpContext context) +21
   System.Web.UI.Page.ProcessRequest(HttpContext context) +49
   ASP.productlist_aspx.ProcessRequest(HttpContext context) in c:\windows\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files\root\e529ecf2\18fea36a\App_Web_q6lqkkxv.13.cs:0
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +181
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +75


Version Information: Microsoft .NET Framework Version:2.0.50727.5448; ASP.NET Version:2.0.50727.5456

Posted 31-May-12 21:59pm

Gaurav K Mishra

Updated 23-Sep-19 0:03am

Richard MacCutchan

v2

Add a Solution

Comments

pataoengineer 1-Jun-12 4:30am

Are you running the same website binary on the same machine (but published to different application)? I used to encounter this kind of problem when I duplicated webapp binaries into different application for testing purpose.

2 solutions

Solution 3

Please add this code in your web.config page :

C#

<system.web>
    <machinekey validation="SHA1" validationkey="A1B2C3D4E5F6F6E5D4C3B2A1A1B2C3D4E5F6F6E5D4C3B2A1A1B2C3D4E5F6F6E5D4C3B2A1A1B2C3D4E5F6F6E5D4C3B2A1A1B2C3D4E5F6F6E5D4C3B2A1B2C3D4E5">
decryption="Auto" decryptionKey="A1B2C3D4E5F6F6E5D4C3B2A1A1B2C3D4E5F6F6E5D4C3B2A1" />
</machinekey></system.web>

Posted 6-Aug-13 22:58pm

Mas11

Comments

CHill60 7-Aug-13 9:58am

Doesn't add anything to taha bahrami's solution a year ago

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

taha bahraminezhad Jooneghani · Accepted Answer · 2012-05-31T22:39:00

Solution 1

its all about machine key!
set a machine key in your config file!
use this link to generate a machine key:
machine key generator[^]

Posted 31-May-12 22:39pm

taha bahraminezhad Jooneghani

Comments

taha bahraminezhad Jooneghani 1-Jun-12 4:43am

viewstate use machine key to encrypt , because u don't set it it use the host machine key and this problem happen!
if u set it in your config file problem will solved! it happens to me too!

Gaurav K Mishra 1-Jun-12 4:55am

thanks for reply I am trying it.

taha bahraminezhad Jooneghani 1-Jun-12 5:02am

and put the machine key under system.web section!

Gaurav K Mishra 1-Jun-12 6:19am

Is The Machine Key generator secure? any security threat from that?

taha bahraminezhad Jooneghani 1-Jun-12 10:24am

and you don't say,is your problem solved?
and if solved whay not a 5?:)

taha bahraminezhad Jooneghani 1-Jun-12 10:22am

yes this is absolutely ok , I use this, but remember that encryption of viewstate isn't secure at all , you shouldn't put valuable thing in view state and read this tip for more security with page submition:
http://www.codeproject.com/Tips/345268/The-Power-Of-ViewState-in-ASP-NET

Gaurav K Mishra 1-Jun-12 14:12pm

thanks it is working well...