If available on the current page, portlet, or dialog box, you can click 
Email or Send Email to manually send an email message.
P6 provides the following email notifications. Follow the summary steps below (or, if needed, see more detailed task topics) to configure automatic Email notifications for a particular item.
Requirements:
In general, you should have an email address stored in your user account to send Email and recipient users should have an email address stored in their user accounts to receive email. The email accounts are required in order to send email to users by selecting them from a list. They are then automatically applied to the email message. However, it is also possible to manually enter a recipient's email address in the Email dialog box just before sending the message.
To use the Notifications feature, your administrator will enable settings in Primavera P6 Administrator and configure it for use with a mail server.
After notifications are enabled, each individual can specify their personal notification preferences enumerated below:
- To configure automatic email to a resource when that resource is added or removed from an assignment, select the Send Email to resources upon adding or removing assignments option in the General section of the Global tab of the My Preferences page.
- To receive email notifications about issues, configure the Issues section of the Global tab of the My Preferences page. You can be notified about issues based on an issue's priority level. For example, you can be notified only when an issue's priority is listed as "high." You can also be notified when issues are modified, or when issues are assigned a specific issue code. You can be notified about issues for projects based on whether you have project access rights, issue access rights, if you are the Project Owner or Issue Owner, or if you are assigned as a resource to that activity.
- To automatically send email to a designated temporary project manager delegate assigned to approve timesheets, select the check box on the Assign Project Manager Delegate dialog box. This will notify the delegate of their temporary assignment to review timesheets and will list the designated projects.
- To automatically send email to a designated temporary resource manager delegate assigned to approve timesheets, select the check box on the Assign Resource Manager Delegate dialog box. This will notify the delegate of their temporary assignment to review timesheets and will list the designated projects and individual resources.
- To automatically send email to a resource about a rejected timesheet, reject the timesheet on the TimeSheet Approval page from within P6. You will be prompted to send a notice.
- Administrators can configure BPM to notify a user when a project workflow is awaiting that user's approval.