Program works using debugger but dumps in background or dialogue

hello experts,

I have a confusing issue. When I run the program in the debugger it works fine but when I run it in the background or dialogue mode I get an ABAP dump with the following message:

CL_GUI_CUSTOM_CONTAINER----------------------------CP " CNTL_ERROR"

What does this error mean and what code could I insert in the program to avoid this error.

Thank you.

Regards

David Dittmer