Last Updated: 20 Jul 2021 07:50 by ADMIN
Release R3 2021
Created on: 13 Jul 2021 17:15
Category: Scheduler/Reminder
Type: Bug Report
RadScheduler: Displaying an appointment with a subject of empty html tags <> will crash the program.

1) create new project with a radScheduler

2) add a new appointment with a subject of: <>

3) program will crash with System.InvalidOperationException: 'Collection was modified after the enumerator was instantiated.'


The program will crash even if you have additional text before the "<>" but having text after it will allow the program to continue running however, none of the text after the "<>" will display.

1 comment
Dess | Tech Support Engineer, Principal
Posted on: 14 Jul 2021 08:49

Hello, Logan,

Following the provided information, I was able to replicate the error message:

I have approved this bug report.You can track its progress, subscribe for status changes and add your comments on the following link - feedback item.

I have also updated your Telerik points.

Currently, the possible solution that I can suggest is to disable the HTML text rendering:

        public RadForm1()


        private void radScheduler1_AppointmentFormatting(object sender, SchedulerAppointmentEventArgs e)
            e.AppointmentElement.UseHtml = false;

I hope this information helps. If you need any further assistance please don't hesitate to contact me. 

Dess | Tech Support Engineer, Principal
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