Monitor  （33:276）  Block  not  found !

Help on Message 33:276

Description:
The block could not be cut or deleted in the PLC because it is a system block or a system function.
ONLINE: Message from the module:
  D204 = No linked block in given storage medium.
  D209 = At least one listed block not available on the module.
  D20E = No block available reading directory of PLC.
  EPROM = The block does not exist on the Memory Card/MMC.
Remedy:
OFFLINE:  Save block in database.
ONLINE:  Download block to the module.
EPROM:  Save block on the Memory Card/MMC.


求助，为什么会出现这个情况呢？

我应该怎么解决啊？？

谢谢！