OPT3001: Initialising I2C connection with MSP432 Launchpad not working , ends at "static void defaultISR(void)" function (Sensor BoosterPack)

I am trying to read Lux values from the OPT3001 Sensor (on the Sensors BoosterPack) with my MSP432 Launchpad. I establish an I2C connection, but the task I created never executes. Using the debugger I find that after calling the function "sensorOpt3001Init()" the program jumps to this part.

/* This is the code that gets called when the processor receives an unexpected  */
/* interrupt.  This simply enters an infinite loop, preserving the system state */
/* for examination by a debugger.                                               */
static void defaultISR(void)
{
    /* Fault trap exempt from ULP advisor */
    #pragma diag_push
    #pragma CHECK_ULP("-2.1")

    /* Enter an infinite loop. */
    while(1)
    {
    }

    #pragma diag_pop
}

My code looks like this 

uint16_t RawOptValue = 0;
QueueHandle_t xOPTQueue;

 xOPTQueue = xQueueCreate(100, sizeof(float));

    initI2C();
    if(xOPTQueue != NULL)
    {
    xTaskCreate(read_OPT, "OPT Measurement", configMINIMAL_STACK_SIZE, NULL, 1, NULL);
    }

    vTaskStartScheduler();



This is the task I create

void read_OPT(void* pvParameters)
{
    float ConvertedOptValue = 0.0;

    sensorOpt3001Init();

    for(;;){
        sensorOpt3001Enable(true);
        vTaskDelay(pdMS_TO_TICKS(1000));

        //Test if the sensor works, blink LED 100ms if it does

        if( sensorOpt3001Test() == true )
        {
            configTOGGLE_LED();
            vTaskDelay(pdMS_TO_TICKS(100));
            configTOGGLE_LED();
        }

        sensorOpt3001Read(&RawOptValue);
        sensorOpt3001Convert(RawOptValue, &ConvertedOptValue);

        sensorOpt3001Enable(false);


        // Send data to a queue

        if( xOPTQueue != NULL ){
        xQueueSend(xOPTQueue, (void *) &ConvertedOptValue, 0);
        }
    }
}


Does anyone have an idea why this happens? If I remove the function "initI2C()", I end up in 

void I2C_masterSendMultiByteStart(uint32_t moduleInstance, uint8_t txData)
{
    //Store current transmit interrupt enable
    uint16_t txieStatus = EUSCI_B_CMSIS(moduleInstance)->rIE.r & UCTXIE;

    //Disable transmit interrupt enable
    BITBAND_PERI(EUSCI_B_CMSIS(moduleInstance)->rIE.r, UCTXIE_OFS) = 0;

    //Send start condition.
    EUSCI_B_CMSIS(moduleInstance)->rCTLW0.r |= UCTR + UCTXSTT;

    //Poll for transmit interrupt flag.
    while (!BITBAND_PERI(EUSCI_B_CMSIS(moduleInstance)->rIFG.r, UCTXIFG_OFS))
        ;

    //Send single byte data.
    EUSCI_B_CMSIS(moduleInstance)->rTXBUF.r = txData;

    //Reinstate transmit interrupt enable
    EUSCI_B_CMSIS(moduleInstance)->rIE.r |= txieStatus;
}

and the program stops at the while statement. Is anyone familiar with this behaviour and can explain why this happens?