Debugging LPC1778- "Cannot stop CPU"

I have CrossStudio 2.2, a CrossConnect USB (version 4) with SWD adapter and a board.

Connection from the SWD adapter to the board is made with my regular 20 wire ARM JTAG cable.

Target properties in CrossStudio are:

• Target Interface Type = SWD
• Adaptive Clocking: Auto/Yes/No
• JTAG Clock divider: Tried various settings from 1 to 16.

Did not manage to debug my program on the board. When I press F5, I always get "Cannot stop CPU".

My program is a simple main loop created from the "An executable for NXP LPC1778" template. STARTUP_FROM_RESET is defined in preprocessor.

What can I do?

Regards,

SJ