Server Error in '/' Application.

Collection was modified; enumeration operation may not execute.

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.InvalidOperationException: Collection was modified; enumeration operation may not execute.

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:


[InvalidOperationException: Collection was modified; enumeration operation may not execute.]
   System.ThrowHelper.ThrowInvalidOperationException(ExceptionResource resource) +56
   System.Collections.Generic.Enumerator.MoveNextRare() +14917366
   PRIO.Nisat.Templates.Wagstaff.Controls.ThemeBrowser.RenderThemeList() +789
   PRIO.Nisat.Templates.Wagstaff.Controls.ThemeBrowser.Page_Load(Object sender, EventArgs e) +90
   System.Web.UI.Control.OnLoad(EventArgs e) +106
   System.Web.UI.Control.LoadRecursive() +68
   System.Web.UI.Control.LoadRecursive() +162
   System.Web.UI.Control.LoadRecursive() +162
   System.Web.UI.Control.LoadRecursive() +162
   System.Web.UI.Control.LoadRecursive() +162
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3785


Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.7.4076.0