DB error after changing config.php

  • I had this installed and working.  I changed the config.php to use a different image rather than banner.png.   When I did that, I just got blank pages so I reverted back to the old config.php (I had saved it).  However, now I get a db error.  Please see link

    I don't understand what is causing this error.  Just to be certain I hadn't gone mad when I thought I saved the old config.php, I started again with config.php.template, changed just my database details but still get the same error.
    Any ideas?

    • Never mind about this error - turns out my web hosting company was doing upgrade/maintainance and moved things around just at this moment.  I have had to change 'localhost' in the config file to 'mysql.interdns.co.uk' to make it work but it does again.