On the Auto Import tab in PokerTracker 3, select 888 Poker from the site list on the left hand side, then click the 888 Poker Configuration tab to the right.
If you do not see your hand history folder listed, click the Auto Detect button. This should add the correct folder to the Directories Configuration. If it doesn't, you can manually select the folder using the Add button.
If you play at more than one 888 Poker site, make sure that all of your sites' hand history folders are listed here.
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Tip: If you do not see 888 Poker listed, check the Show Hidden Sites option.
If you would like PokerTracker 3 to start importing hands from 888 Poker whenever you start auto importing, enable the Automatically Start With Auto-Import option.