Symptoms
Consider the following scenario:
This message is shown in the following screen shot.
Additionally, if you search for email items in your mailbox, the search results may display the following text at the bottom of the results:
This message is shown in the following screen shot.
If you click the More link, additional items that meet your search criteria are displayed in the search results. This occurs because Outlook retrieves the additional items from your mailbox on the server that's running Exchange Server.
Note This behavior can also occur in the RSS Feeds folder in your Exchange mailbox.
- You're using Microsoft Outlook 2019, Outlook 2016, Outlook 2013 or Outlook for Office 365.
- You're connected to an Exchange Server mailbox.
Notes
- If you're running Outlook 2019, Outlook 2016, or Outlook for Office 365, this account might be your primary mailbox or another mailbox to which you have delegate access or another permission. This might be an additional, shared, or auto-mapped mailbox, or public folders.
For more information about this issue in Outlook 2019, Outlook 2016, or Outlook for Office 365 related to shared mailboxes or public folders, see the following article in the Microsoft database:3140747 Only a subset of items are synchronized in shared mailboxes or public folders in Outlook 2016
- If you're running Outlook 2013, the account must be your primary account.
- If you're running Outlook 2019, Outlook 2016, or Outlook for Office 365, this account might be your primary mailbox or another mailbox to which you have delegate access or another permission. This might be an additional, shared, or auto-mapped mailbox, or public folders.
- Your Exchange email account is configured to use Cached Exchange Mode.
There are more items in this folder on the server
Click here to view more on Microsoft Exchange
This message is shown in the following screen shot.
Additionally, if you search for email items in your mailbox, the search results may display the following text at the bottom of the results:
Showing recent results...
More
This message is shown in the following screen shot.
If you click the More link, additional items that meet your search criteria are displayed in the search results. This occurs because Outlook retrieves the additional items from your mailbox on the server that's running Exchange Server.
Note This behavior can also occur in the RSS Feeds folder in your Exchange mailbox.
Cause
This behavior occurs because the Cached Exchange mode Mail to keep offline setting is configured to a value other than All. For example, the following screen shot shows a profile that's configured to use Cached Exchange Mode and the Mail to keep offlinesetting is set to a default value of 12 months.
Note Outlook 2019, Outlook 2016, Outlook 2013 and Outlook for Office 365 provide the options of 1, 3, 6, 12, or 24 months, or All. Outlook 2019, Outlook 2016, and Outlook for Office 365 provide the additional options of 3 days, 1 week, and 2 weeks.
In the default configuration, depending on the size of your hard disk, Outlook synchronizes only 1, 3, or 12 months of email to your Offline Outlook Data (.ost) file from the Exchange server.
If your Mail to keep offline setting is set to 12 months and you have email items in your Exchange mailbox that are older than 12 months, those items reside only in your mailbox on the server. Therefore, if you can't connect to the Exchange server, you may be unable to retrieve items outside the range that's specified by the Cached Exchange Mode synchronization setting until you reconnect with the server.
Note This setting does not affect the number of items that are synchronized with folders of the following types:
Note Outlook 2019, Outlook 2016, Outlook 2013 and Outlook for Office 365 provide the options of 1, 3, 6, 12, or 24 months, or All. Outlook 2019, Outlook 2016, and Outlook for Office 365 provide the additional options of 3 days, 1 week, and 2 weeks.
In the default configuration, depending on the size of your hard disk, Outlook synchronizes only 1, 3, or 12 months of email to your Offline Outlook Data (.ost) file from the Exchange server.
If your Mail to keep offline setting is set to 12 months and you have email items in your Exchange mailbox that are older than 12 months, those items reside only in your mailbox on the server. Therefore, if you can't connect to the Exchange server, you may be unable to retrieve items outside the range that's specified by the Cached Exchange Mode synchronization setting until you reconnect with the server.
Note This setting does not affect the number of items that are synchronized with folders of the following types:
- Calendar
- Contacts
- Tasks
- Journal
- Notes
- Outbox
- Shared or delegated (only for Outlook 2013)
More Information
To reduce the effect of the Outlook offline data file (.ost), the default number of months that are configured for your profile varies by the size of your hard disk. The following table provides the different default values for different hard disk sizes.
If you have to change the number of selected months of email to synchronize with your cached mode .ost file, follow these steps:
This message is shown in the following screen shot.
Under similar conditions, if you search for items in your mailbox and you don't have connectivity with the Exchange server, the following message is displayed underneath the search results:
In this message, <x> represents the value that's configured for the cached mode Mail to keep offline setting.
An example of this message is shown in the following screen shot.
The Group Policy template files for Outlook 2016, Outlook 2019 and Outlook for Office 365 are Outlook16.admx and Outllk16.adml. The files for Outlook 2013 are Outlk15.admx and Outlk15.adml. If you use Group Policy to manage this setting, the following registry data is used by Outlook:
| Hard disk size | Default value for "Mail to keep offline" |
| Less than or equal to 32 GB | 1 month |
| Greater than 32 GB, but less than 64 GB | 3 months |
| Equal to or greater than 64 GB | 12 months |
If you have to change the number of selected months of email to synchronize with your cached mode .ost file, follow these steps:
- Start Outlook.
- On the File tab, click Account Settings, and then click Account Settings.
- On the E-mail tab, double-click your Microsoft Exchange account.
- In the Change Account dialog box, drag the Mail to keep offline slider to the desired number of months or to All to synchronize all email messages.
- Click Next.
- Click OK when you're prompted to restart Outlook to complete the configuration change.
- Click Finish.
- Restart Outlook.
Working Offline
If you don't have connectivity with the Exchange server, the following message is displayed in a folder if there are older items on the server that were not synchronized with your .ost file:There are more items in this folder on the server
Connect to the server to view them
Connect to the server to view them
Under similar conditions, if you search for items in your mailbox and you don't have connectivity with the Exchange server, the following message is displayed underneath the search results:
Server unavailable. <x> months of results shown.
An example of this message is shown in the following screen shot.
Feature Administration through Group Policy
The cached mode Mail to keep offline setting is maintained in the Outlook profile settings in the Windows registry. If you want to administer this setting by using Group Policy, you can use the Group Policy templates. These are available from the following Microsoft websites, depending on your version of Office:Office 2016, Office 2019, or Outlook for Office 365: http://www.microsoft.com/en-us/download/details.aspx?id=49030
Office 2013: http://www.microsoft.com/download/details.aspx?id=35554
Office 2013: http://www.microsoft.com/download/details.aspx?id=35554
The Group Policy template files for Outlook 2016, Outlook 2019 and Outlook for Office 365 are Outlook16.admx and Outllk16.adml. The files for Outlook 2013 are Outlk15.admx and Outlk15.adml. If you use Group Policy to manage this setting, the following registry data is used by Outlook:
Key: HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\x.0\Outlook\Cached Mode
DWORD: SyncWindowSetting
Value: integer value (Decimal) specifying the number of months (use only the following values)
DWORD: SyncWindowSetting
Value: integer value (Decimal) specifying the number of months (use only the following values)
0 = All (whole mailbox)
1 = 1 month of email items
3 = 3 months of email items
6 = 6 months of email items
12 = 12 months of email items
24 = 24 months of email items
NoteThe x.0 placeholder represents your version of Office (16.0 = Office 2016, Office 2019 or Outlook for Office 365, Office 2019 or Outlook for Office 365, 15.0 = Office 2013).
Note The Outlook 2016, Outlook 2019 or Outlook for Office 365 user interface (UI) lets you set the Mail to keep offline setting to the additional values of 3 days, 1 week, and 2 weeks. The May 3, 2016, update for Outlook 2016 allows you to set these additional values by using the SyncWindowSettingDays registry data. For more information about how to configure Outlook 2016 with these additional values, see the following article in the Microsoft Knowledge Base:
1 = 1 month of email items
3 = 3 months of email items
6 = 6 months of email items
12 = 12 months of email items
24 = 24 months of email items
NoteThe x.0 placeholder represents your version of Office (16.0 = Office 2016, Office 2019 or Outlook for Office 365, Office 2019 or Outlook for Office 365, 15.0 = Office 2013).
Note The Outlook 2016, Outlook 2019 or Outlook for Office 365 user interface (UI) lets you set the Mail to keep offline setting to the additional values of 3 days, 1 week, and 2 weeks. The May 3, 2016, update for Outlook 2016 allows you to set these additional values by using the SyncWindowSettingDays registry data. For more information about how to configure Outlook 2016 with these additional values, see the following article in the Microsoft Knowledge Base:
3115009 Update lets administrators set additional default Sync Slider windows for new Exchange accounts in Outlook 2016