getting error message while uploading

Board:arduino UNO
Servo:SG90
error:Arduino: 1.8.5 (Windows 10), Board: “Arduino/Genuino Uno”

Sketch uses 5590 bytes (17%) of program storage space. Maximum is 32256 bytes.
Global variables use 278 bytes (13%) of dynamic memory, leaving 1770 bytes for local variables. Maximum is 2048 bytes.
avrdude: ser_open(): can’t open device “\.\COM1”: The system cannot find the file specified.

Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.

This report would have more information with
“Show verbose output during compilation”
option enabled in File → Preferences.

code:/*NOTE: Four Servos of the Robotic Arm are connected to 4 PWM Pins of Arduino
and these 4 servos are named a, b, c and d.

If you want to control servo a, then type “90a/”,
where “90” is the PWM value (range is 0 - 255),
“a” means servo a and “/” is string parse delimiter.

Some other examples: 100a/ or 120b/ or 40c/ or 25d/
*/

String readString;
int x=90, y=90, z=90, p=90;
#include <Servo.h>
Servo myservoa, myservob, myservoc, myservod;

void setup()
{
Serial.begin(9600);

myservoa.attach(3);
myservob.attach(5);
myservoc.attach(6);
myservod.attach(9);
myservoa.write(x);
myservob.write(y);
myservoc.write(z);
myservod.write(p);
}

void loop()
{
if (Serial.available())
{
char m = Serial.read();
if (m == ‘/’)
{
if (readString.length() >1)
{
Serial.println(readString);

int temp = readString.toInt();

Serial.print("writing Angle: ");
Serial.println(temp);
if(readString.indexOf(‘a’) >=0)
{
if (temp>x)
{
for (int i=x; i<temp; i++)
{
myservoa.write(i);
delay(10);
}
x=temp;
}
else
{
for (int i=x; i>temp; i–)
{
myservoa.write(i);
delay(30);
}
}
x=temp;
}
//////////////////////////////////////////////////////////////////////////////
if(readString.indexOf(‘b’) >=0)
{
if (temp>y)
{
for (int i=y; i<temp; i++)
{ myservob.write(i);
delay(10);
}
y=temp;
}
else
{
for (int i=y; i>temp; i–)
{
myservob.write(i);
delay(10);
}
y=temp;
}
}
///////////////////////////////////////////////////////////////////////
if(readString.indexOf(‘c’) >=0) //myservoc.write(n);
{
if (temp>z)
{
for (int i=z; i<temp; i++)
{myservoc.write(i);
delay(10);}
z=temp;
}
else
{
for (int i=z; i>temp; i–)
{
myservoc.write(i);
delay(10);
}
z=temp;
}
}
/////////////////////////////////////////////////////
if(readString.indexOf(‘d’) >=0)
{
if (temp>p)
{
for (int i=p; i<temp; i++)
{
myservod.write(i);
delay(10);
}
p=temp;
}
else
{
for (int i=p; i>temp; i–)
{
myservod.write(i);
delay(30);
}
}
p=temp;
}

readString="";
}
}
else
{
readString += m;
}
}
}

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Select the port of your Arduino from the Tools > Port menu. If that menu is grayed out or the port of your Arduino board is not shown then one of the following may be the cause:

  • You may need to install the driver for the USB-serial chip on your Arduino. Determine which chip is used on your Arduino and install the driver.
  • You may be using a charge-only or defective USB cable. Test your cable on another device to confirm that it works for data.