Hi @Trish White ,
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Support for Office 2013 ended on April 11, 2023 and there will be no extension and no extended security updates. For your better user experience, it is recommended that you use a newer version of office. For more information, please refer to: End of support for Office 2013.
However, a couple of days ago, I’ve noticed the “Sent Items” folder has disappeared from Outlook on my PC.
Have you done any operations before that?
And can you find the Sent folder in [Gmail]/Sent Mail folder?
If not, considering the influence of some views, please try a command to reset the view settings: win+R> type: outlook /cleanviews.(This command will delete all custom view settings. If you need to keep other view settings, please remember to back up.)
If it's doesn't work, 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.
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