The HeaderExtEnum type indicates the way the
  left/right or/and top/bottom header extends. The 
AllowHeaderExt
  property specifies the way the left/right or/and top/bottom header extends (
  for all pools). The 
AllowHeaderExt
  property specifies the way the left/right or/and top/bottom header extends (
  for specified pool). The HeaderExtEnum type supports the following values:
 |  | Name | Value | Description |  | 
 |  | 
exHeaderExtUndefined | -1
 | 
 No extension is defined for the pool's header.
 |  | 
 |  | 
exCornerEmpty | 0
 | 
 No corner is assigned to the header.
 |  | 
 |  | 
exCornerTopLeftExtHeaderLeft | 1
 | 
 The left-header extends its content to top-left corner.
 |  | 
 |  | 
exCornerTopLeftExtHeaderTop | 2
 | 
 The top-header extends its content to top-left corner.
 |  | 
 |  | 
exCornerTopRightExtHeaderRight | 256
 | 
 The right-header extends its content to top-right corner.
 |  | 
 |  | 
exCornerTopRightExtHeaderTop | 512
 | 
 The top-header extends its content to top-right corner.
 |  | 
 |  | 
exCornerBottomRightExtHeaderRight | 65536
 | 
 The right-header extends its content to bottom-right corner.
 |  | 
 |  | 
exCornerBottomRightExtHeaderBottom | 131072
 | 
 The bottom-header extends its content to bottom-right corner.
 |  | 
 |  | 
exCornerBottomLeftExtHeaderLeft | 16777216
 | 
 The left-header extends its content to bottom-left corner.
 |  | 
 |  | 
exCornerBottomLeftExtHeaderBottom | 33554432
 | 
 The bottom-header extends its content to bottom-left corner.
 |  |