If your account is hosted on an Exchange server and the Free/Busy information couldn't be retrieved by Outlook 2007/2010/2013/2016/2019, the Free/Busy information for other users will be displayed as slash marks (/).

Note: Free/Busy information missing can be easily confused with Outside of working hours. If you see Free/Busy displayed in light-grey blocks, check your Working Hours in Outlook.

free busy

There can be several possible causes for this:

  1. Autodiscover record is missing or set up incorrectly
    You need to make sure that the Autodiscover CNAME record has been created for your domain. Outlook 2007/2010/2013/2016/2019 discovers the Availability Service URL using the AutoDiscovery feature in the Exchange environment.

    Read the Knowledge Base article on What Is An Autodiscover Record And Why Do I Need It? for more information.

  2. Default Permissions for the Calendar are missing
    Check the permissions on the Calendar you would like to view Free/Busy information for. The permissions should be set to Free/Busy time to be displayed correctly: right-click on Calendar > Properties > Permissions.
    free busy

  3. Outlook Calendar/nickname cache is corrupt
    Try to start Outlook with the cleanfreebusy switch:
    Start > Run > type outlook.exe /cleanfreebusy
    Note: works only in Outlook 2007/2010
    free busy

    If this did not help, the Outlook autofill entry might be corrupted: when creating a new meeting, start typing the name of the affected user and, when it appears, click on the X next to it to delete the autofill entry.

    Read the Knowledge Base article on How To Reset The Outlook Nickname Autocompletion Cache for more information.