avrdude: stk500_recv(): programmer is not responding - Cant upload a sketch

Hello, I am using my Arduino Nano controllers now for one year withhout any problems. But out of nowhere since 3 days I cant upload a sketch on my controllers anymore. Compiling works but it just says "Uploading" for like 5 minutes and nothing happens. The error code is the following:

Arduino: 1.8.12 (Windows 10), Board: "Arduino Nano, ATmega328P (Old Bootloader)"


avrdude: Version 6.3-20190619
         Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
         Copyright (c) 2007-2014 Joerg Wunsch

         System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf"

         Using Port                    : COM7
         Using Programmer              : arduino
         Overriding Baud Rate          : 57600
         AVR Part                      : ATmega328P
         Chip Erase delay              : 9000 us
         PAGEL                         : PD7
         BS2                           : PC2
         RESET disposition             : dedicated
         RETRY pulse                   : SCK
         serial program mode           : yes
         parallel program mode         : yes
         Timeout                       : 200
         StabDelay                     : 100
         CmdexeDelay                   : 25
         SyncLoops                     : 32
         ByteDelay                     : 0
         PollIndex                     : 3
         PollValue                     : 0x53
         Memory Detail                 :

                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           eeprom        65    20     4    0 no       1024    4      0  3600  3600 0xff 0xff
           flash         65     6   128    0 yes     32768  128    256  4500  4500 0xff 0xff
           lfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           hfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           efuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           lock           0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
           calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00
           signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00

         Programmer Type : Arduino
         Description     : Arduino
         Hardware Version: 2
         Firmware Version: 1.16
         Vtarget         : 0.0 V
         Varef           : 0.0 V
         Oscillator      : Off
         SCK period      : 0.1 us

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.00s

avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: reading input file "C:\Users\LUCDEC~1\AppData\Local\Temp\arduino_build_125657/RGB_Code.ino.hex"
avrdude: writing flash (1328 bytes):

Writing | avrdude: stk500_recv(): programmer is not responding
####avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding
Problem beim Hochladen auf das Board. Hilfestellung dazu unter http://www.arduino.cc/en/Guide/Troubleshooting#upload.

This is one code that usually should work on the Nano and that Im trying to use now:

int red_light_pin= 11;
int green_light_pin = 10;
int blue_light_pin = 9;
void setup() {
  pinMode(red_light_pin, OUTPUT);
  pinMode(green_light_pin, OUTPUT);
  pinMode(blue_light_pin, OUTPUT);
}
void loop() {
  RGB_color(255, 0, 0); // Red
  delay(1000);
  RGB_color(0, 255, 0); // Green
  delay(1000);
  RGB_color(0, 0, 255); // Blue
  delay(1000);
  RGB_color(255, 255, 125); // Raspberry
  delay(1000);
  RGB_color(0, 255, 255); // Cyan
  delay(1000);
  RGB_color(255, 0, 255); // Magenta
  delay(1000);
  RGB_color(255, 255, 0); // Yellow
  delay(1000);
  RGB_color(255, 255, 255); // White
  delay(1000);
}
void RGB_color(int red_light_value, int green_light_value, int blue_light_value)
 {
  analogWrite(red_light_pin, red_light_value);
  analogWrite(green_light_pin, green_light_value);
  analogWrite(blue_light_pin, blue_light_value);
}

I dont know anymore what to do. I read like 50 posts in different forums, used 4 different Arduino Nanos that worked perfectly like a few days before, reinstalled Arduino IDE 3 times and did nearly every trick that was posted anywhere in the forums. Nothing works.

I can see my Nanos in the device Manager, already reinstalled the Nanos software a few times and use the right COM port. Nothing helps. I already did many tricks like pressing the reset button one the nano while compiling and letting it go as soon it Uploads but that doesnt work.

Is there anyone that had the same problem and can tell me an unwritten or untold solution? Or is there a gamma ray burst ongoing that I am not aware of and is destroying my Nanos? Any help would be appreciated.

I don't know if this will help or not:

On 6/9/2020, Arduino Support was e-mailed about the IDE not working correctly all of a sudden. They sent this out on 6/10/2020:

We had a problem on our package_index.json file which caused the current error and it has prevented the IDE to start. Now the package_index.json file has been fixed, but to recover a working installation you must delete once again the package_index.json and restart the IDE as usual.

You can find the package_index.json usually in the following folders: Windows:

[color=#2b2e2f]remove file C:\Users\YourUsername\AppData\Local\Arduino15\package_index.json
remove folder C:\Users\YourUsername\AppData\Local\Arduino15\cache[/color]

Mac:

[color=#2b2e2f]remove file /Users/YourUsername/Library/Arduino15/package_index.json
remove folder /Users/YourUsername/Library/Arduino15/cache[/color]

Linux:

[color=#2b2e2f]remove file: /home/YourUsername/.arduino15/package_index.json
remove folder /home/YourUsername/.arduino15/cache[/color]

Please note that the problem that prevents the IDE to start has already been fixed for the next releases, that's the reason why the Nightly/Beta Builds are not affected, and also the reason why we did not detect the problem earlier,

Which bootloader are you using ?

Arduino: 1.8.12 (Windows 10), Board: "Arduino Nano, ATmega328P (Old Bootloader)"

Have you tried selecting other Nano versions? Worst case, perhaps install a new bootloader into your Nanos, using a Programmer, or an Arduino set up as a Programmer.