This could be because your InCopy is in a different view than Layout View. To switch to Layout View, close all your InCopy windows and open InCopy on its own (open InCopy without opening any chapters from CtrlPrint). Navigate to View menu in InCopy and select Layout View. After this, you can try to open the document from CtrlPrint.
Another common cause of this is that there is some security software (e.g. AppLocker) that is blocking access to the CtrlPrint plug-ins. Please make sure that the following are whitelisted:
- %appdata%\Ctrl
- %temp%\Ctrl
This issue may also be related to the machine not meeting Adobe's minimum specs for InCopy.