Issue: attachfile index error

ErrorException: Undefined index: attachfile - /var/www/html/forum/vault/core/view/ui/edit/attach/vw.php:90
Generated By: rizwank, Today at 1:34 PM
Stack Trace
#0 /var/www/html/forum/vault/core/view/ui/edit/attach/vw.php(90): XenForo_Application::handlePhpError(8, 'Undefined index...', '/var/www/html/f...', 90, Array)
#1 /var/www/html/forum/vault/core/view/ui/edit/vw.php(92): vw_UI_Edit_Attach_View->before_editor_blocks(Object(vw_UI_Area_Controller), Array)
#2 /var/www/html/forum/vault/core/controller/ui/edit/vw.php(605): vw_UI_Edit_View->edit(Object(vw_UI_Area_Controller))
#3 /var/www/html/forum/vault/core/controller/ui/create/vw.php(116): vw_UI_Edit_Controller->edit(Object(vw_UI_Area_Controller))
#4 /var/www/html/forum/vault/core/controller/ui/area/vw.php(89): vw_UI_Create_Controller->create(Object(vw_UI_Area_Controller))
#5 /var/www/html/forum/vault/core/controller/ui/area/vw.php(48): vw_UI_Area_Controller->create()
#6 /var/www/html/forum/vault/core/controller/ui/stack/vw.php(154): vw_UI_Area_Controller->execute()
#7 /var/www/html/forum/wiki_index.php(92): vw_UI_Stack_Controller->execute()
#8 {main}
Request State
array(3) {
  ["url"] => string(86) "http://forum.xxxx.com/wiki_index.php?title=threadwiki&do=create&itemtypeid=8"
  ["_GET"] => array(3) {
    ["title"] => string(10) "threadwiki"
    ["do"] => string(6) "create"
    ["itemtypeid"] => string(1) "8"
  }
  ["_POST"] => array(0) {
  }
}