Click the bell icon on the upper right to view notifications. You can find:
Alerts about starred campaigns: Campaign Manager lists alerts about items related to starred campaigns, including alerts about creatives that need click tags or placements that have no default ads, or the advertiser's Floodlight configuration.
In-product messages: Announcements about upcoming changes, temporary UI issues, or other important updates are stored in your list of notifications.
Use notificationsWhen you have notifications about specific items, use the notification links to view them. For example, when you have a notification about a creative, Campaign Manager provides a link to view the creative.
When you're done with a notification, click Mark as read underneath it. This greys out the message. The rest of your notifications will remain highlighted.
Choose notifications for items in starred campaigns
When you star a campaign, Campaign Manager shows it at the top of your campaign list. This way you can easily find your most commonly used campaigns. Starring campaigns also triggers notifications for the campaign.
How to star campaigns: Click Campaigns in Campaign Manager and select the star icon by your campaign. The stars are right next to the checkboxes.
How to browse starred campaigns: Use the scrollbar or arrows to cycle through your list of campaigns at the top. You can hide your starred campaign boxes with the Hide starred campaigns button. They will no longer appear at the top, but you will still be able to find them in your campaign list.
Campaign Manager lists notifications about starred campaign items in the "Notifications" pane. Here's how to choose which notifications you see there:
Click the bell icon in the upper right.
Switch alerts ON or OFF to change whether appear in your notifications list. Note that this only changes whether these alerts are listed in the "Notifications" pane. Your alerts will always appear next to the items themselves in Campaign Manager.