Encontrou a solução no site da ms
In case you have removed a POP account from the Outlook, the data file associated with the account will not be removed automatically. We have to close the data file by right clicking on it. In case this personal folder is set as default personal folder, then you may not be able to close it. You must set a different data file as default data file and then close it. Open Outlook > Click on File > Account settings > Data files > Choose a new data file > Click on default > Select the problem data file and click on remove.
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