hang while USB receive

Hi to all the members. I have been very impressed by the members answers which encourages me to post my query first time. Good job.

I am trying to communicate between the USB and the device STM32. I have configured the packet size to 64 both receive and sent.

I am transmitting the packet from the PC to board (packet length > 64). In this I got success by receieving the 64 packet each time with termination condition ";" at the end.

Now I also want to transmit a packet gretaer than 64 to PC. but everytime the communication hangs.

the code is pasted below. hope it helps

Board code:
printf("%s\n\r",OutReport);
if((OutReport[0]=='!') || (OutReport[0]=='K'))
{ while(count_buffer > 0)
{ if(OutReport[0]=='K')
{ for(i=0;i<64;i++)
{ tempINbuffer[i] = OutputBuffer[init];
init++;
} sprintf(InReport,"%s",tempINbuffer);
printf("\n\rInreport: %s",InReport);
init = init + 1;
count_buffer = count_buffer - 64;
OutReport[0]='S';
} }
} OutputBuffer contains a data greater than 64 characters.

Visual Basic 6 code:
Usb_Tx = "K;"
Call WriteReport
Usb_Rx_temp = ""
receive_flag = 1
While receive_flag <> 1
Call ReadReport
Usb_Rx_temp = Usb_Rx_temp & Usb_Rx
receive_buff = VBA.StrConv(Usb_Rx, vbFromUnicode)
For i = 0 To 63
If receive_buff(i) = 59 Then
receive_flag = 1 MsgBox receive_buff(i)
End If
Next Usb_Tx = "K;"
Call WriteReport
Wend
Text1.Text = Usb_Rx_temp

I apologise for the formatting as this message box doesnt support formatting.

Thanks for your time.