Hi @Federico Coppola ,
I noted that I can open email without issues using Exchange Online.
Do you mean that this issue only happen in Outlook desktop client and can work fine in Outlook web mail?
I did some research about your pop-up message: Contacting Server for Information, and most of the similar cases show that it might be related to your Outlook desktop client settings. In order to conduct further researches about your issue, please check the suggestions below:
- In order to ensure that the functions of the Outlook client itself can work properly, please make sure that you have fully repaired and updated your Outlook client.
- Outlook Automatic Downloads setting might cause similar issues as well. Please check your Automatic Downloads setting and modify them like below, then restart your Outlook desktop client and test again to see if the issue could be resolved.
- As I know, other third party software and Anti-Virus programs might also influence Outlook desktop client. So, to exclude possible factors as much as possible, I would suggest you to temporarily exit all the other programs in windows and run Outlook alone in safe mode (Press Win + R, type “outlook /safe”, press Enter.) and see if the issue continues.
Hope this can be helpful.
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