"The security validation for this page is invalid" error when updating objects through SharePoint object model

This error is often encountered when SharePoint OM is used to update site/web/list objects from within a web context. Some thing so basic as the code below could fail:

 using (SPSite site = new SPSite("https://moss"))
{
    using (SPWeb web = site.OpenWeb())
    {
        SPList list = web.Lists["List1"];
        list.Title = "List2";
        list.Update();
        web.Update();
    }
}

Setting the "AllowUnsafeUpdates" properties of both the SPSite and SPWeb objects to "true", mostly will resolve this issue out if you are using a code similar to above within a webpart or an ASP.NET web application. When you are running from the context of a separate web application make sure the application pool identity running your ASP.NET web application is the same as the one that's running SharePoint's site. Below is a code that fixes the "security validation for this page is invalid" error.

 using (SPSite site = new SPSite("https://moss"))
{
    site.AllowUnsafeUpdates = true;
    using (SPWeb web = site.OpenWeb())
    {
        web.AllowUnsafeUpdates = true;
        SPList list = web.Lists["List1"];
        list.Title = "List2";
        list.Update();
        web.Update();
    }
}

Thought we might actually prevent some support calls by posting this :)

Comments

• Anonymous
  November 18, 2008
  The comment has been removed

• Anonymous
  February 16, 2009
  How can i add this code in masterpage

• Anonymous
  January 05, 2010
  I have just recently written a post with more info on this error. http://www.simple-talk.com/community/blogs/charleslee/archive/2010/01/05/85440.aspx

• Anonymous
  July 14, 2010
  Thanks.....very sweet and short solution.

• Anonymous
  January 06, 2011
  hey.. nice article.. but yes one more check need to be done .. verify whether you have FormDigest control added on page from which request is sent .. :)

• Anonymous
  August 24, 2011
  Obviously Bhushan did the application development exam ;) Question should be why you want to bypass a security validation. This is a bypass of security not a fix imo