Hi @S475 ,
Welcome to our forum!
Outlook not sending emails
In order to verify, are the messages stuck in Outbox? According to my search, there are several reasons for the issue, here is an official document for your reference:
I can't send or receive messages in Outlook
Why the installer keeps crashing immediately?
- Are you installing windows update? If so, the Office installation has to wait until the update process has finished with the Windows Installer.
- Have you installed other version office such as office 2013 on the computer? Please check it via Start > Control Panel > Program > Program and feature. More information about Office Installation, refer to this article: Troubleshoot installing Office
If you still need further help on this, feel free to contact us.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.