Reasons a sent fax could be stuck in Sending status:

  1. AUTHORIZATION: You may need to re-authorize the app under Fax Configuration tab under active admin user (or user with proper permissions). There are variables as to why you would need to refresh authorization, for example when there is a change in authorized user, anything in your faxing process/Salesforce has changed, an org refresh, or updated package install. After you do this step, sent fax records will either start to be sent within 24 hour period or you may need to recreate the sent fax records after refreshing authorization.
    1. If you receive an error message when trying to authorize the app that refers to “this site cannot be reached”, please review this article to resolve.
  2. FILES OR USER PERMISSION ISSUE: If a fax is getting stuck in Sending status for no apparent reason and files are used instead of attachments, the issue might be that a user which authorized the app doesn’t have access to the file which is being sent. For more information about this, please review this article. Also, each user that is sending a fax needs proper access to Sent Fax, Received Fax and any other objects/fields being used in faxing process, and needs to have a profile permission Send Outbound Messages enabled. This permission is located in Setup > Users > Profiles > your target profile > System Permissions System, and under System while in System Permissions.
    1. If you are using “Documents” rather than File format and the sent fax is getting stuck in “sending” status then the user may not have access to the Document being sent and they may be owned by another user. To resolve, you can add the “modify all documents” permission to the user profile. This permission should allow the user to have proper access to the Documents and successfully send the fax with no issues.
  3. AUTOMATION/INACTIVE USER: If you have configured an automatic process for faxing (using process builder, flow, apex, or any other means of automation), and sent faxes are stuck in Sending status, you should check if the running user is active. It is possible that one user may be set as a default user for the specific automation, and it got deactivated. Also, check the files issue from point 2. If you would like assistance to review automation setup, we offer app premium support as a service.
  4. API CALL LIMIT: You may have hit your daily API call limit. Go to Setup > Company Settings > Company Information > Show API Requests > Last 24 Hours. See what the limit is and see if you went past it. If you did, you will need to wait till your 24 hour mark is over to start with new limit. You can submit case to Salesforce to increase your daily API call limit if needed.