Problem:

The contacts in Outlook fail to sync with the Contacts app.

Cause:

1. Power Saving Mode may have been enabled. Therefore, data isn't synced in order to save power.
2. Auto-sync data may have been disabled.

Solution:

1. Go to Optimizer > Battery and disable Power Saving mode.

   

2. Go to Settings > Users & accounts, touch theMore menu in the upper right corner, and enable Auto-sync data, as shown in the following figure.

   

3. Open Outlook, touch the G button in the upper left corner, touch the Settings icon, touch your mail account, and enable Sync contacts, as shown in the following figure. (Make sure that your Google mail account has been added in the Outlook app.)

   

4. To check whether your account has been added in the Contacts app for syncing contacts, openthe Contacts app, touch the More menu in the upper right corner (indicated by "1" in the following figure), then touch Settings (indicated by "2").

   

   Touch Accounts, select your account, and check whether the Sync Contacts option is enabled, as shown in the following figure.