I just upgraded from v4.9.0 to v5.0.0

when i loaded the site fresh after uploading all the new files, it began the installation updates to update my database and some other local files, everything said 'success' and to 'click here to go to your site'

when i go to my website's home page, now all i see is this DNN error and dont know how to fix it, help!!?!?!?

DotNetNuke Error: - Version 05.00.00

An error has occurred. DotNetNuke.Services.Exceptions.PageLoadException: Could not load type 'DotNetNuke.UI.Utilities.MSAJAX' from assembly 'DotNetNuke.WebUtility, Version=3.2.0.0, Culture=neutral, PublicKeyToken=null'. ---> System.TypeLoadException: Could not load type 'DotNetNuke.UI.Utilities.MSAJAX' from assembly 'DotNetNuke.WebUtility, Version=3.2.0.0, Culture=neutral, PublicKeyToken=null'. at DotNetNuke.UI.WebControls.DNNMenu.LoadPostedJSON() at DotNetNuke.UI.WebControls.DNNMenu.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.AddedControl(Control control, Int32 index) at System.Web.UI.ControlCollection.Add(Control child) at DotNetNuke.UI.Skins.NavObjectBase.InitializeNavControl(Control objParent, String strDefaultProvider) at DotNetNuke.UI.Skins.Controls.Nav.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Control.AddedControl(Control control, Int32 index) at System.Web.UI.ControlCollection.Add(Control child) at DotNetNuke.Framework.DefaultPage.Page_Init(Object sender, EventArgs e) at System.Web.UI.Control.OnInit(EventArgs e) at System.Web.UI.Page.OnInit(EventArgs e) at DotNetNuke.Framework.PageBase.OnInit(EventArgs e) at System.Web.UI.Control.InitRecursive(Control namingContainer) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) --- End of inner exception stack trace ---

i deleted the file "'/bin/DotNetNuke.WebUtility.dll", and copied/pasted a fresh version of it from the extracted DNN v5.0 folder located elsewhere on my computer

everything works fine now

i am having the same problem:

DotNetNuke Error: - Version 05.00.00

System.NullReferenceException: Object reference not set to an instance of an object. at DotNetNuke.UI.Utilities.MSAJAX.Serialize(Object Obj) at DotNetNuke.UI.Utilities.ClientAPI.SerializeClientVariableDictionary(Page objPage, Dictionary`2 objDict) at DotNetNuke.UI.Utilities.ClientAPI.CAPIPreRender(Object Sender, EventArgs Args) at System.Web.UI.Control.OnPreRender(EventArgs e) at System.Web.UI.HtmlControls.HtmlInputHidden.OnPreRender(EventArgs e) at System.Web.UI.Control.PreRenderRecursiveInternal() at System.Web.UI.Control.PreRenderRecursiveInternal() at System.Web.UI.Control.PreRenderRecursiveInternal() at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

tried recopying the DLL as mentioned above but did not help.