Office 365 Calendar via EWS connection troubleshooting

This article describes potential issues with Office 365 Calendar via EWS integration and how these issues can be fixed. If you’re still having problems, please contact us and we will be happy to assist you.

I cannot connect. What should I do?

This may be due to temporary communication problems with the Office 365 API. Please try the following:

  1. Make sure cookies are enabled on your browser.
  2. Verify that you can log in to your Office 365 account.
  3. Try to connect again from OnceHub. 

Even if your credentials are correct, the connection might not be successful due to various Office 365 configurations. In that case, you may need to provide additional information (Figure 1).

Figure 1: Connect to Office 365 Calendar with additional information

The value to enter in the User name field depends on your Office 365 configuration, and may be any of these three options:

  1. Leave blank—not required for many Office 365 servers.
  2. Try entering your email again, which some Office 365 servers accept as a username.
  3. Enter your full Domain\UserName that you would use to sign into other Windows systems:
    • Your organization's domain. This can be the Windows domain that you sign into when entering internal systems or your PC. Try searching your organization's instructions about connecting your email client or mobile phone to your mailbox. It can be any name selected by your system administrators.
    • Make sure you use a backslash (the symbol \ and not /) between the domain and the user name.
    • Your UserName is the ID you use to access your internal systems. Use your internal ID, with which you log into internal systems (Windows Active Directory name or User Principal Name).

Click the Connect button. If you're still not connected, make sure you have entered all the values as above, making sure all the formats and slashes are in the right places.

If you're still seeing issues, please contact us and we'll be glad to assist. Please also check with your Office 365 admin to ensure that your Office 365 user has access to the Office 365 API.

Connection errors after a successful connection

Once a successful connection was established, it may fail due to reasons described below. 

ImportantDuring a connection failure, ScheduleOnce Booking pages cannot accept bookings. This measure is taken to prevent the possibility of double bookings. 

To re-enable bookings and meetings, you must either restore the connection by reconnecting, or disconnect your calendar by clicking the Disconnect link and then reconnect again.

Possible connection failure reasons include:

  • Change of password: If your Office 365 password was changed or your app password was deleted, you will need to reconnect. Sign in to your OnceHub Account, go to the left sidebar and click Profile -> Calendar connection. Then, click the Reconnect your Office 365 Calendar button.
  • Change of Office 365 or network configuration: Your administrator may have changed the Office 365 settings, firewall settings, or access permissions. Contact your IT support to find out about such changes.
  • Temporary disconnection: Sometimes a connection may be temporarily lost, for example during network maintenance. Once the issue is resolved, the connection is restored automatically.

Configuration issues in ScheduleOnce

Busy time in Office 365 Calendar is not blocking my availability in ScheduleOnce

If busy time is not blocking your availability, you can check the following settings:

New bookings are not added to my Office 365 Calendar

  1. Go to ScheduleOnce and select Setup -> relevant Booking page -> Associated calendars.
  2. Make sure your calendar is marked as the Main booking calendar or an Additional booking calendar.
    Learn more about the Associated calendars section

I cannot see my scheduled booking in my Office 365 Calendar

In your Office 365 Calendar, make sure that you've selected the calendar that your meeting was scheduled in. Find it in the calendar list in the left bar and click it to select it. 

In ScheduleOnce, you can also select the activity in the Activity stream, then click the action menu (three dots) in the right-hand pane and select View Calendar event (Figure 2).

Figure 2: View Calendar event

Other issues 

Contact OnceHub support if you experience other issues.

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