connection error to ESP 8266 - access denied - ...

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Dear commnity




after having successfully installed the binaries on the ESP with this tool - the ESP8266-Flasher :: ESP-IDF

we stuck ..


see the protocolll 



Detecting chip type... ESP8266
Chip is ESP8266EX
Uploading stub...
Running stub...
Stub running...
Configuring flash size...
Auto-detected Flash size: 4MB
Erasing flash (this may take a while)...
Chip erase completed successfully in 12.4s
Flash params set to 0x0340
Compressed 589360 bytes to 385922...
Wrote 589360 bytes (385922 compressed) at 0x00000000 in 34.7 seconds (effective 135.9 kbit/s)...
Hash of data verified.



now we want to do first tests - i. e. connect to the board. 

with the uPyCraft-IDE we tried to connect to the board - but this failed with the following lines.. 

could not open port 'COM3': PermissionError(13, 'Zugriff verweigert', None, 5)
could not open port 'COM3': PermissionError(13, 'Zugriff verweigert', None, 5)
serial not open
could not open port 'COM3': PermissionError(13, 'Zugriff verweigert', None, 5)

any idea how t o skip this errors - and to connect to the board!? 

thanks for any and all help in advance

  • Facepalm 1
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hello and good day 

 _ after having tried some thing - the biest just started to work .

serial allready opened ... and i guess that i have managed to connect to the board and to work on it. 

btw: i have in the device folder 

but no main folder (guess that this will be loaded with my first script) 

see the attached image to see that all is woriking now at least regarding this tutorial


have a great day. 


btw. where to download the newest v ersion of uPCraft - i have running version 1.0 
and besides that: i have mused and thougtht that it wold be  a good idea to get other IDEs working with the ESP such as 


but do i need to install the ArduinoIDE too !? 
love to hear from you 


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