Any time you get an error in LV you can right click on the error cluster indicator and do a "Explain Error".
If you do this for the error code you reported, the explanation says that it was a framing error.
In serial communications, a framing error indicates that the hardware was not able to detect a start bit, data then the stop bits that comprise a frame.
This prompts me to suggest that you check you port setting on the serial port. You want to make sure you are setting the port for the correct;
Number of start/stop bits,
Baud rate
data bits
parity (just for good measure)
and hardware handshaking.
I hope this helps,
Ben