Forum Discussion

ArjanBroekhuizen's avatar
ArjanBroekhuizen
Iron Contributor
Jul 23, 2025

Difference between Outlook Classic and Outlook Web

Hi all, On off our users has a problem with managing calendars in Outlook. When she uses Outlook Classic to manage a delegated calendar, she gets an error that she has no rights for that. But when...
exchange online
office 365
outlook
Semo_NF's avatar
Semo_NF
Copper Contributor
Jul 25, 2025

Exchange Online and Outlook Web are both runnig in the Cloud. -- The Classic Client is installed on a Device which has a WIndows Firewall, maybe also a Company Firewall between the Client and the Cloud. I Clould be possible that there is something blocked, so that the neccesary communication isn´t working. https://learn.microsoft.com/en-us/microsoft-365/enterprise/urls-and-ip-address-ranges?view=o365-worldwide

  • ArjanBroekhuizen's avatar
    ArjanBroekhuizen
    Iron Contributor
    Jul 29, 2025

    Hi Semo_NF​ 

    Thanks for your reply. I don't think that it is a firewall issue. Other users don't report problems with managing delegated calendars.