Import Error: Class 'Link" not found

Hi guys,
We have recently moved our site across to a new host provider ( and am trying to import some Meetings from our previous site.
Upon importing the .csv file, a small number of Meetings are imported before we receive the attached error message.
Can someone please point me in the right direction of the file / error in question? I have Notepad++ and just need to find that line 672!!

So I’ve managed to find the link2.php file on my site and opened it using Notepad++.
Scrolled down to line 672 and found the following message -

" //Below are functions not used directly and exist for backwards compatibility with customizations, will be removed in a later version

/* returns array of keys for duplicate checking, first check for an index of type alternate_key, if not found searches for
 * primary key.
public function _get_alternate_key_fields($table_name) {
    $indices=Link::_get_link_table_definition($table_name,'indices');  - THIS IS LINE 672
    if (!empty($indices)) {
        foreach ($indices as $index) {
            if ( isset($index['type']) && $index['type'] == 'alternate_key' ) {
                return $index['fields'];
    //bug 32623, when the relationship is built in old version, there is no alternate_key. we have to use join_key_lhs and join_key_lhs.
    $relDef = $this->relationship->def;
    if (!empty($relDef['join_key_lhs']) && !empty($relDef['join_key_rhs']))
        return array($relDef['join_key_lhs'], $relDef['join_key_rhs']);

Can anyone advise why this is causing an error with my new site / installation, which is version 7.2.2, hosted by