Cannot download to CP1H

[Sergei Troizky 26]

A function block and its only instance have been deleted from the project, which was then downloaded to the controller with no problem. The machine is up and running, however ... Since this download, it is possible to go online, compare, and upload, but the processor cannot be switched to programming mode, neither manually from CXP nor by download procedure. Both timeout with message "Cannot change the controller mode to Program. The controller still may be switching its mode". This is not the literal text (I am posting from home) but the meaning is exactly this. Any ideas? The FB was inactive prior to download.

[BobB 58]

? Have never seen that before.

[Mendon Systems 22]

On the older CPM2 and CQM1 units you could power it off and disconnect the battery for 30 minutes to reset to the factory configuration. I'm not sure if that still works with the CP1 series because they now store the programs in flash memory.