I did not see any issue in above code. But what condition you are checking to show the comment - No Issues in voltage?

Yes, if you are allocating memory using 'new' to your RichEdit, then yes you have to release it. But you have to do it before your parent window (in this case your CDialog) is destroyed. Override OnDestroy (WM_DESTROY) and destroy your RichEdit followed by 'delete' (to release heap memory) and then call the CDialog::OnDestroy().