Disappear attachment file from task - Dynamic CRM 2015

Hello everyone,

I face a problem on crm 2015 when i want to attach file on a task. First of all, i create a task and i save it. When i go to attach a file in notes section all is good, i can attach file without any problem. When i go to close the task or finish the task or convert the task to opportunity the attach file seems to disappear from notes section and notes section seems to be stuck on loading.

Any help?

 Yours sincerely,