I saw a warning that scheduled tasks were not running. I confirmed that the cron entry was correct. I decided to delete it and then added it again.

Now I am receiving emails with this. I receive the same if I manually try and run task.php from a shell command line.

Any thoughts?

 

Cache-Control: no-cache, no-store, must-revalidate, max-age=0, s-maxage=0
Expires: 0
Content-type: text/html; charset=UTF-8

Not at command line

I think I solved this by using "php-cli" rather than "php" in the crontab entry.

I do not understand why this suddenly stopped working after working fine for years.

 

I do not understand why this suddenly stopped working after working fine for years.

You would need to ask your server administrator or hosting provider what has transpired.