I can’t reply to a post in Apple discussions

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As few posters return to their old posts to look for late responses , focusing on old posts is not very productive. Focus on the newest threads..

What you encountered is common when people come here from a search engine. Search engines, unless you limit the search string to the current year, mine up too many locked, old posts.

Rather than use a search engine, bookmark this site map:

Site Map - Apple Community

and use its topic lists to work the posts made within the last week or so.

It is greyed out because it is a dormant thread, that has not seen activity for quite some time. Such threads are locked after a period of inactivity.

Based on the image, the reply button is greyed out because the discussion has been closed. Apple has a policy of closing discussions that have been inactive for a certain period of time to avoid irrelevant or outdated posts.

In this case, the discussion was started on March 1, 2018, and the last post was on March 1, 2018. It's likely that Apple closed the discussion some time after that.

You can try to start a new discussion about the same topic, or you can search for a more recent discussion about the same issue.

Here are some additional tips:

* Make sure you are logged in to the Apple Support Communities with your Apple ID.

* If you are still having trouble, you can contact Apple Support for assistance.

Here are some resources that you may find helpful:

* Apple Support Communities: Official Apple Support Community

* Apple Support: Official Apple Support

I hope this helps! Let me know if you have any other questions.