Thank you for reaching out to us through the Microsoft Q&A platform.
Based on your inquiry, it appears that you are encountering an error while attempting to install Nginx on an Azure virtual machine designated for Azure Fundamentals training. The error message suggests a problem with the "Custom Script" extension required to execute the installation script.
Please ensure that there are no typographical errors in the publisher parameter within the 'az vm extension set' command. It should be Microsoft.Azure.Extensions, not Micrsoft.Azure.Extensions.
To ensure accuracy and prevent errors, you can copy the command directly from the learning path by selecting the "Copy" option and then paste it into Cloud Shell using the right-click paste method.
We recommend activating a new sandbox environment to confirm that the issue is not specific to your current setup. Create a new VM within the new sandbox and attempt to install Nginx using the Custom Script extension, following the instructions provided in the documentation.
Please refer to the screenshot below depicting the correct publisher parameter and the successful execution of the 'az vm extension set' command following VM creation:
If you are still encountering difficulties, please inform us in the comments section. We are here to assist you.
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