Hi @Mantas Skorupskas ,
Based on the information you provided, it seems that the issue is with the configuration settings of your old version of Outlook. The error message “log in to the incoming mail server (imap): failed to connect to the server” indicates that the client is unable to establish a connection with the IMAP server.
You mentioned that you have tried turning off the firewall, but it did not resolve the issue. In that case, it is possible that the antivirus software installed on your computer is blocking the client-server connection. You may want to temporarily disable the antivirus software and check if it resolves the issue.
It is also possible that Outlook has incorrect configuration setting, double-check the incoming and outgoing server settings, port numbers, and SSL/TLS options.
If the issue persists, you may want to consider upgrading to the latest version of Outlook, please refer to Microsoft’s official documentation for detailed instructions on how to update Microsoft Office.
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