Sometimes the data file for a mailbox can get partially corrupt. Common examples are clicking on an email then only to show a blank screen or clicking on an email in a folder listing only to show the wrong email after.
Below are two articles that can help both Outlook and MacMail users.
How to use the Inbox Repair tool (scanpst.exe) for Outlook
How to use Rebuild for MacMail
- Select the Mailbox
- Choose Rebuild from the Mailbox menu
- There is a rebuild option for every IMAP email client because this happens to everyone at some point