Adding Public Folders to Outlook Cache for Searching

Tags faculty staff

​How to add a public folder to be cached and used with Instant Search:

  1. Open Outlook.
  2. Click Folders in the bottom navigation pane.
  3. On the left side of the Folder module, find the folder to index under the Public Folders - list.
  4. Right-click on the folder and select Add to Favorites.
  5. Rename the folder and add subfolders if preferred, and click Add.
  6. Right-click on Public Folders - ​ and click Data File Properties.
  7. Click Advanced.
  8. In the window that opens, go to the Advanced tab.
  9. Check Use Cached Exchange​ Mode and Download Public Folder Favorites.
  10. Click OK.
  11. This should index the public folder and allow for searching.

Caching too many Public Folders

Public Folder search is an incredible tool, especially for collaborative work. However, it can also create serious problems for Outlook and search  too many public folders are added to favorites.
Public Folders tend to be on the larger side, so be very careful that the selected public folders cache are not very big. The data in these cached folders will be downloaded into an ost-file onto the local hard drive. If that file is exceedingly large, it may result in poor search performance and even connection problems to the Exchange Server. The key is to make sure to not to cache too many folders, and if only one Public Folder is cached, then make sure it is not huge.
If after setting it all up Outlook is running slower than usual or connection problems are occurring, then try limiting what type of files and content are being indexed.​
For additional support, contact the Technology Service Desk at,, or submit a request through the Technology Service Catalog.