Error loading Python Environment for Tello Camera

Hi, I don’t know how to get around an error code on a step in the course: Tello Camera Control with DroneBlocks Python App.

I followed along OK until the 3rd section "Download and Run the DroneBlocks Python Code (5:16) following the windows installation instruction video @

When I attempt to run for the first time it fails to get flask up and running with errors shown below.

Can you help please?

Regards Keith

Error message


** On entry to DGEBAL parameter number 3 had an illegal value ** On entry to DGEHRD parameter number 2 had an illegal value ** On entry to DORGHR DORGQR parameter number 2 had an illegal value ** On entry to DHSEQR parameter number 4 had an illegal value ImportError: numpy.core.multiarray failed to import Traceback (most recent call last):

File “”, line 3, in from import Camera File “C:***\DroneBlocks-Tello-Camera-With-Python-OpenCV-master\lib\”, line 1, in import cv2

File “C:\Users***\AppData\Local\Programs\Python\Python37\lib\site-packages\”, line 5, in from .cv2 import * ImportError: numpy.core.multiarray failed to import

Here is a ‘pip list’ showing I had successfully loaded packages/dependencies up to that point:

pip list
Package Version

click 7.1.2
Flask 1.1.2
itsdangerous 1.1.0
Jinja2 2.11.2
MarkupSafe 1.1.1
numpy 1.19.4
pip 20.1.1
setuptools 47.1.0
Werkzeug 1.0.1
WARNING: You are using pip version 20.1.1; however, version 20.3 is available.
You should consider upgrading via the ‘c:\users***\appdata\local\programs\python\python37\python.exe -m pip install --upgrade pip’ command.

That’s really strange. I just fired up a new project on my PC and got everything running fine. Here is my pip list:

What version of Python are you running? Also if you run the following command can you tell me the path to your Python…

where python


One other thing I’d like you to try. Go to your python prompt and try to import cv2 like explained in the video course. Do you get an error or does it import successfully?

I am having the same issue. Apparently a recent windows update caused an error with numpy.

They say it should be fixed mid Jan.


Matt, do you have a link that we can look through?

I got it to work following this suggestion @

" I found out! For some reason the numpy 1.19.4 version has some bug on windows, just uninstall and install a previous version

pip uninstall numpy

and then

pip install numpy==1.19.3

As this source guided:"

Thanks kinman, champion!