"MySQL server has gone away" issue

Hi there...
My Zenphoto site has started throwing the following error...

Fatal error: MySQLi Error: ( SELECT * FROM [prefix]news WHERE date<="2017-12-31 08:59:49" AND show="1" AND expiredate<="2017-12-31 08:59:49" AND expiredate!="0000-00-00 00:00:00" AND expiredate IS NOT NULL ) failed. MySQLi returned the error MySQL server has gone away in /mounted-storage/home117a/sub005/sc62105-HHGW/www/mywebsitename/zp-core/functions-db-MySQLi.php on line 78

I get similar when trying to login to admin.

When i go to mywebsite/zp-core/setup.php I get the message

 You must restore the setup files from the 1.4.12 [c1d7e8900b] release.

What may be the cause and how do I do this?
Many thanks
Mark