By default RichTextEditor automatically detect the MIME type of the files you upload, and rejects the file if the file-extension does not match the mime type ("The file is corrupt or has an incorrect extension"). You can turn it off by setting this property to "false".

Example

<?php   
    $rte=new RichTextEditor();   
    $rte->Text="Type here"; 
    $rte->EnableMimetypeChecking=false;   
    $rte->ID="Editor1";    
    $rte->MvcInit();
    echo $rte->GetString();  
    // use $_POST["Editor1"]to retrieve the data  
?> 

See Also

Editor Class | RTE Namespace