Ensure to enable the add-in for ALL users in Exchange Admin Center
The steps below apply to Office 365 Exchange Online, Exchange Server 2013, Exchange Server 2016
- Log in to Exchange Admin Center on-prem or Exchange Admin center in Office 365 Console.
- Click on Organization > Add-ins.
- Make sure that Symantec Email Submission is on the list of add-ins.
- To enable users to use the add-in, select Make this add-in available to users in your organization check box.
- Optional, enabled by default. Use this setting if you want to allow your users to turn off the add-in.
- Optional, disabled by default. Use this setting if you want to allow your users to turn on the add-in.
- Mandatory, always enabled. Users can’t disable this add-in. Use this setting if you don’t want your users to turn off the add-in.
If the add-in is not visible on the list of add-ins, see Install Outlook Email Submission Add-in.
Check that the add-in is enabled for the user
The following steps apply to Outlook 2013, Outlook 2016, OWA.
- Open Outlook
- Click on File > Manage add-ins
- Make sure that Symantec Email Submission is on the list of add-ins and has a check mark under "Turned on" field.
If the add-in is not visible on the list of add-ins, see Install Outlook Email Submission Add-in.
Additional checks for On-Premise Exchange environments:
- Make sure that “OAuthAuthentication” is enabled for EWS (Exchange Web Services) virtual directory. It can be verified by running the following command in Exchange Management Shell:
#>Get-WebServicesVirtualDirectory -Identity "EWS (Default Web Site)" | Select OAuthAuthentication | fl
Expected Output:
OAuthAuthentication : True
The option OAuthAuthentication is enabled by default. For more information about enabling this option, see Set-WebServicesVirtualDirectory.
- Make sure that EWS Access is enabled for the users who are going to use the add-in. The following command can obtain the EWS related configuration:
#>Get-OrganizationConfig | Select EWS* | fl
By default, EWS is enabled for all users. The expected output for the default configuration is:
EwsAllowEntourage:
EwsAllowList:
EwsAllowMacOutlook :
EwsAllowOutlook:
EwsApplicationAccessPolicy :
EwsBlockList:
EwsEnabled : True
For more information about allowing EWS Access to users, see Controlling client application access to EWS in Exchange.
- Ensure the digital certificates used in EWS are signed by a Certificate Authority (CA) and not self-signed certificates (Certificates signed by the same entity whose identity it certifies).