Thanks for letting me know. As I wrote in the previous post, I know they aren't working and I'm trying to figure it all out because I haven't done anything to Dropbox to cause this. I know the search has changed as well, something I mentioned in the previous post. I can't change that, lamentably.
Update: Dropbox decided that free users would no longer be able to share files with links as of March 15, 2017. They claim they sent out email about this, but no one seemed to have received these messages. They are discontinuing public folders for business users in September, so it's not like spending $13 a month would solve the problem. Besides, I don't want to reward Dropbox's jerky behaviour by signing up for a monthly account. I would still have to do all kinds of work to get the links working again.
Anyone have suggestions for a reliable, affordable file hosting site" I'm a die hard Mac user. Any suggestions would be greatly appreciated!