anytime I go in and try to update Umbraco CMS User info, I get the following YSOD below. Is anyone else experiencing this issue? many thanks!

Server Error in '/' Application.

Method not found: 'Void umbraco.BusinessLogic.User.ClearApplications()'. 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.MissingMethodException: Method not found: 'Void umbraco.BusinessLogic.User.ClearApplications()'.

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:

[MissingMethodException: Method not found: 'Void umbraco.BusinessLogic.User.ClearApplications()'.] umbraco.cms.presentation.user.EditUser.SaveUser_Click(Object sender, ImageClickEventArgs e) +0 System.Web.UI.WebControls.ImageButton.OnClick(ImageClickEventArgs e) +134 System.Web.UI.WebControls.ImageButton.RaisePostBackEvent(String eventArgument) +204 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3804

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.18067