Android errors while compilation and downloading

I encounter very strange problem…after installation the Arduino project (BLEWIFIConfig.ino) everything run smoothly, upload and operated as expected.
After a while, I tried to compile and download again the project on the development board, but fails finding couple exe files (pick.exe, pad.exe).
I found them in the Git, download them and now the compilation is OK.
Trying to upload the project to the development board, fails with the “Cannot run program “REMOVE/upload_image_tool_windows.exe”: CreateProcess error=2, The system cannot find the file specified” message.
The same problem occurs with Blink.ino project, which tells me that the problem is in the Arduino.
Now - two questions, please:

  1. How come the files deleted? by whom?
  2. Where should I located the upload_image_tool_windows.exe file, so the Arduino will find it when it comes to upload the project?

Thanks and sorry for the long explanations

Please remove the board and re-download the board using board manager.

All the tools are automatically installed while board manager download the board, it can be found in your “C → user → your username → AppData → Arduino15 → packages → realtek → amebad → tools” if you are using windows

Normally only you and arduino IDE have access to these files, so it’s so either bcos of an incomplete update, or you was attacked by some malware

The path of the tools are documented in the platform.txt under the hardware folder-- can be found in the same folder as the tools folder