For each affected account, click the gear at the top right, pick Edit account details, and select Complete in the Tracking Method box.
Then go to Edit > Preferences > Investment transactions and un-check the Enable Simple Investing box.
If you just un-check the setting in Preferences and Quicken checks it again, the accounts will switch back to Simple.
Dave Mayer said: The "Tracking Method" box does not show when I go to my investment account details. How do I get to the "Tracking Method" box?