Hello @Cédric Perion ,
Apologies for the delay in response. I just came across your query in community.
It is little difficult to troubleshoot this with little information but I'll give you a few quick points that you could check and confirm.
Are you using Windows 11 multi-session image? If yes, then which Windows 11 Version from the Marketplace do you use?
Is the task bar visible if you create a direct RDP connection and log on with a local admin user?
Before investigating any further, could you please answer the above requested details. Also, please install the latest cumulative updates, restart the VM and also delete the FSLogix profile of the affected user after the update and before he logs in the first time after the update.
Hope this helps. Looking forward to hearing back from you. Thanks :)
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