copying from an pointed address

Hello,
I'm trying to implement a code which copies a part of a string
which is pointed to by a char (*outr_message), and adds it to an unsigned-char
(UART1_error_format).

For example: if *outr_message is "e97" so UART1_error_format will be err97.

the current code is:

void Serial_Output_Full_Reset(char *outr_message)
{
        unsigned char UART1_error_format[5] = "err";

        //prepare the message
        set_message_in_transbuffer(String_Message, outr_message, NULL, NULL, 0, 0);
        #if __RS485__
                if (&outr_message[1] == 'e')                        // converting 'eXX' to 'errXX'
                {
                        strncpy(UART1_error_format, outr_message + 2, 2);
                        UART1_error_format[5] = '\0';
                        random_write(0 ,0 , nooutr, UART1_error_format, 2);
                }
        #endif
}

after compiling there's an error appearing:

new_meas_proc.c(52): warning C214: 'Argument': conversion: pointer to non-pointer

I've tried several ways to fix the warning, which is connected to the strncpy function
I believe, since I've entered to the function 'random_write' correct variables types:

void random_write(float Treal, float Emiss, unsigned char Outr,unsigned char Err,
        unsigned char Scale);

What should be done to fix the warning? is a conversion from char to unsigned char also needed?
Thanks much,
Amitai
pointers are quite confusing...