# Getting start with Arduino ESP8266 certificate generation error **URL:** \ **Category:** HiveMQ Cloud\ **Created:** [November 29, 2021, 10:59am UTC](https://community.hivemq.com/t/getting-start-with-arduino-esp8266-certificate-generation-error/844 "2021-11-29T10:59:33Z")\ **Posts on this page:** 1\ **Showing post:** 16
**Author:** ![rickqinj](https://avatars.discourse-cdn.com/v4/letter/r/e47c2d/32.png) [@rickqinj](https://community.hivemq.com/u/rickqinj)\ **Post date:** [January 16, 2022, 4:13am UTC](https://community.hivemq.com/t/getting-start-with-arduino-esp8266-certificate-generation-error/844/16 "2022-01-16T04:13:35Z")
**About the exception “ar” not found.** If you get your ESP8266 boards installed via Arduino IDE Board Manager, you may not have the path in your Arduino IDE home folder which the cert download script `certs-from-mozilla.py` requires. However, you can find the folder somewhere else on your system. In my case, I used the software `Everything` to look for the folder `xtensa-lx106-elf` and found the `ar.exe` finally. **About the “openssl” not found.** Actually, it is not necessary to have OpenSSL installed if you’ve had Git installed on your system. As the cert download script needs to access the `openssl.exe` to execute some certificate-related commands, the only thing you need to do is to add the path of the `openssl.exe` to your system PATH variables to make it accessible to the cert download script, that’s it. **Finally, execute the cert download script** Copy the cert download script `certs-from-mozilla.py` to the folder where the `ar.exe` is located. And open the script with Python IDLE and run. After it is completed, you will get a folder `data` with a `certs.ar` file in it. Then, move the folder `data` into your project folder and go on the HiveMQ tutorial. --- _[View the full topic](https://community.hivemq.com/t/getting-start-with-arduino-esp8266-certificate-generation-error/844)._