Usually it means that the thread has been closed and hidden by a moderator. Sometimes it is later reopened though when the moderator has finished his/her work on it.
I get those soemtimes. And yes, sometimes they do mean that the thread has been hidden from our view but there are times when it's just a glitch and refreshing the page might help. And sometimes I will also go and clear out browser history and cookies/cache just in case that's what is causing the problem.
Edit to add that Vanilla Support had posted in another thread that they have been working on the notification issues that some users have been having problems with again with them not getting notified when someone either comments on their page or being mentioned in a post. So that could be the case of you not being able to see the thread that you've commented in. http://forums.thesims.com/en_US/discussion/939668/notifications-not-working-again#latest
@lisasc360 I agree that refreshing the page sometimes helps. But to my experience the reason usually is that the moderator often makes the thread visible again when the moderator has finished editing the thread. But often we don’t get access again until we refresh the page anyway.
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Edit to add that Vanilla Support had posted in another thread that they have been working on the notification issues that some users have been having problems with again with them not getting notified when someone either comments on their page or being mentioned in a post. So that could be the case of you not being able to see the thread that you've commented in.
http://forums.thesims.com/en_US/discussion/939668/notifications-not-working-again#latest
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