Hello George Mouxios,
Greetings! Welcome to Microsoft Q&A Platform.
As said above, you need to be inside of the container in order for the Add Directory button to appear on the toolbar. Click on data to navigate to the container and then you will see Add Directory button.
If still not then check that the Hierarchical Namespace is enabled on your storage account. The ability to create a directory is supported only in storage accounts with Hierarchical Namespace enabled (such as Azure Data Lake Gen2 Storage Accounts).
You can also try from the azure portal you can go inside your container —> click on Upload —> in the Advanced section go to Upload to Folder and provide a folder name —> browse the file to upload —> click on Upload button You should see a folder getting created.
Hope this answer helps! Please let us know if you have any further queries. I’m happy to assist you further.
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