If you had excel adding working and it suddenly does not show the “Dynamics ax” section in excel like the screen below, then please follow the steps below:
Open the Options menu in Excel under file and from the drop down select the COM ad-in and click the GO button.
Next select the Dynamics add-in as shown below and click OK.
As you can see below the new Dynamics AX excel addin tool is activated.
If you are facing issues in getting this by default every time you restart your PC you can try checking with your infrastructure team / system admin to update the registry. Here is a link below that could help:
Happy DAXing ppl.