Step 1: In your Google Admin console (at admin.google.com)…
Step 2: Click Security > Basic settings.
Step 3: Under Less secure apps, select Go to settings for less secure apps.
Step 4: In the sub window, select the Allow users to manage their access to less secure apps radio button.
Once you’ve set Allow users to manage their access to less secure apps to on, affected users within the selected group or Organizational Unit will be able to toggle access for less secure apps on or off themselves.
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