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[Gary]

Can you try the option I gave in this post:

Email body is missing

Can you right-click on the folder and choose Properties > Repair. If the account is a Gmail or Gsuite account, right-click on All Mail and choose Properties > Repair. See if that makes any difference. Otherwise, if the account is setup as IMAP or Exchange, you can remove the account from eM Client, then add it again. Before removing accounts, always make a backup using Menu > Backup.