Hi A.Rade.96,
There are a number of possible reasons why you can't connect but I would check the connection information found in the MB1136 Nucleo board datasheet. Which says:
Follow the sequence below to configure the STM32 Nucleo board and launch the demo software:
1.Check the jumper position on the board, JP1 off, JP5 (PWR) on U5V, JP6 on (IDD), CN2 on (NUCLEO) selected.
2. For correct identification of all device interfaces from the host PC, install the Nucleo USB driver available from the www.st.com/stm32nucleo web page, prior to connecting the board.
3. Connect the STM32 Nucleo board to a PC with a USB cable ‘Type-A to Mini-B’ through USB connector CN1 to power the board. The red LED LD3 (PWR) and LD1 (COM) must light up. LD1 (COM) and green LED LD2 must blink.
4. Press button B1 (left button).
5. Observe the blinking frequency of LED LD2 at different frequencies, by clicking on the button B1.
I had connection problems when I first encountered the Nucleo boards but the steps above sort it out for me. Make sure you check that the demo code works to verify your board is functioning.
I hope this helps.
Kind Regards
reomark