To enable or disable comments on one of your videos, follow the steps below:
Sign in and click your user name in the upper right-hand corner of the page.
Select My Videos from the list of links.
Click the Edit Info button under the video you wish to edit.
Scroll down to choose from the following options:
Allow comments automatically
Allow friends' comments automatically, all others with approval only
Allow all comments with approval only
Don't allow comments
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