Hi @SSSmith ,
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how to repair MS Outlook 2021 professional
Please refer to this official article: Repair an Office application.
when I attempt to send a WORD docx in an email as a .pdf
Do you mean that you save the Word .doc as .pdf and then add it to Outlook email?
If so, based on my test in Outlook, the Outlook doesn't crush or disappear. In order to further confirm if the issue is related to the specific attachment, it's suggested that you could try to send email with other attachment to check if there're any differences.
If the issue persists, it's suggested that you could try the following steps to troubleshooting:
1.Considering the impact of some add ins, It is suggested that you try to start outlook in safe mode(win+R>type: outlook /safe) to check whether it works normally.
2.If this is still the issue in safe mode, it is suggested that you could try to create a new profile (Control Panel>Mail>Show Profiles>add) and add the account for testing to check if there are some differences.
Hope to help you!
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