Autoresponder bounces with "local delivery failed "..."Use of uninitialized value $/"

Symptoms

Someone sends an email to an email address with an autoreponder and they receive a bounce back with something like the following in the bounce response body.

‐‐‐‐‐‐ pipe to |/usr/local/cpanel/bin/autorespond user@domain.tld /home/user/.autorespond

generated by user@domain.tld ‐‐‐‐‐‐

Use of uninitialized value $/ in string eq at /usr/local/cpanel/3rdparty/perl/530/lib/perl5/5.30.0/Carp.pm line 605, <$conf_json> chunk 1.
Cpanel::Exception::JSONParseError/(XID v8mpnf) The system failed to parse the JSON stream data bElement.prototype.appendAfter = function(element) {element.parentNode.insertBefore(this, element.nextSibling);},

Description 

The error output indicates there is an issue with the JSON file used in the autoresponder.

You can check the autoresponder JSON file by doing

cd /home/user/.autorespond

python -mjson.tool user@domain.tld.json

and if you get the output as

No JSON object could be decoded

Then the JSON file is corrupt and needs to be recreated.

Workaround

The mailbox autoresponder needs to be regenerated and while in that cPanel account all the accounts JSON files for autoreponders should be checked just to be sure it is cleared fully.

mkdir /home/user/.autorespond_old
mv /home/user/.autorespond/user@domain.tld* /home/user/.autorespond_old

Then access cPanel and recreate the Autoresponder. The /home/user/.autorespond_old/user@domain.tld file without the extension will have the autoresponder content. That is the file without the .json extension.