diff --git a/lang/en_utf8/error.php b/lang/en_utf8/error.php
index 9d5fe5dd6fb..e8ef851b438 100644
--- a/lang/en_utf8/error.php
+++ b/lang/en_utf8/error.php
@@ -174,6 +174,7 @@ $string['unknowngroup'] = 'Unknown group \"$a\"';
$string['unknownrole'] = 'Unknown role \"$a\"';
$string['unknownuseraction'] = 'Sorry, I do not understand this user action.';
$string['unsupportedevent'] = 'Unsupported event type';
+$string['upgraderequires19'] = 'ERROR: New Moodle version was installed on server, unfortunately upgrade from the previous version is not supported.
Please upgrade first to latest 1.9.x release. You can also return to previous version by reinstalling original files.';
$string['urlnotdefinerss'] = 'URL not defined for rss feed';
$string['userautherror'] = 'Unknown auth plugin.';
$string['userauthunsupported'] = 'Auth plugin not supported here.';
diff --git a/lib/setup.php b/lib/setup.php
index 2be58369f1e..2aaa92354ff 100644
--- a/lib/setup.php
+++ b/lib/setup.php
@@ -291,6 +291,19 @@ global $HTTPSPAGEREQUIRED;
@ini_set('log_errors', '1');
}
+/// detect unsupported upgrade jump as soon as possible - do not change anything, do not use system functions
+ if ($CFG->version < 2007101509) {
+ echo '
+
+
+
+'.get_string('error').'
+
+'.get_string('upgraderequires19', 'error').'
+';
+ die;
+ }
+
/// Shared-Memory cache init -- will set $MCACHE
/// $MCACHE is a global object that offers at least add(), set() and delete()
/// with similar semantics to the memcached PHP API http://php.net/memcache