Using classic Outlook for Windows in business environments
If the messages appear in Online mode, Outlook Web Access, or Outlook Web App, but do not appear in Cached mode for several days, they can be stuck in Outlook’s incoming item processing pipeline. This is associated with the hidden ItemProcSearch folder.
Try these fixes in order:
- Run Outlook with the
/cleanipsswitch.- Exit Outlook.
- Select Start > Run.
- Run:
Outlook.exe /cleanips
- If the issue continues, clear the offline Inbox items and force a resync.
- Start Outlook.
- Right-click Inbox > Properties.
- On the General tab, select Clear Offline Items.
- Select OK when prompted that data was removed from the Outlook data file (.ost).
- Select OK to close Inbox Properties.
- Select Inbox in the Navigation Pane.
- Press Shift+F9 to force resynchronization of the Inbox.
- If Outlook is not automatically downloading mail when it starts, recreate the Send/Receive group.
For Outlook 2010 and later:
- Select File > Options.
- Select Advanced.
- In Send and Receive, select Send/Receive.
- Select the existing group, then select Copy.
- Enter a new group name and select OK.
- Select the old group.
- Clear Include this group in Send/Receive (F9) under both When Outlook is Online and When Outlook is Offline.
- Select Close.
- Restart Outlook.
If the issue is only in Cached mode, these steps target the most common Outlook-side causes.
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