Using classic Outlook for Windows in business environments
Hi @Francesco Mele
Thank you for reaching out to Microsoft Q&A forum.
To provide you a clearer instruction, would you please confirm if you are using Classic Outlook or New Outlook?
We have Classic Outlook icon on the left and New Outlook icon on the right.
You can see that there is a red X for Classic Outlook, which indicates Offline mode is enabled.
You can disable this in Send / Receive tab, click Work Offline again to disable it.
If you do not see this option, try reset the ribbon. Right click on the ribbon and choose Customize Ribbon, next go to Main tab >Send / Receive > Choose Reset. This will reset the ribbon to the default.
For New Outlook, Offline mode is quite different than Classic. You can go to Settings > General > Offline > Turn it off.
You can read here for more details Work offline in Outlook - Microsoft Support
Please provide your Outlook version (Classic or New) so I can assist you better.
I look forward for your reply.
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