Hi @Joe DePaul
Welcome to our forum!
What is your account type (POP/IMAP/Exchange)?
The "Clear Offline Items" option is used to clear the offline items in a specific folder, i.e., to clear the cached items from the OST file. For other folders, we can click on the "Update Folder" button on the "Send/Receive" tab to recover the project.
For other troubleshoot steps, please check the suggestions provided in our official article Sync issues with an .ost file.
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