diff --git a/admin/tool/customlang/cli/export.php b/admin/tool/customlang/cli/export.php
index 29655de7d91..016ca89a4b0 100644
--- a/admin/tool/customlang/cli/export.php
+++ b/admin/tool/customlang/cli/export.php
@@ -36,7 +36,7 @@ Useful for uploading custom langstrings to AMOS or importing or syncing them to
 Options:
 -l, --lang              Comma seperated language ids to export, default: all
 -c, --components        Comma seperated components to export, default: all
--t, --target            Target to copy the zip files to, default: $CFG->tempdir/customlang
+-t, --target            Target directory to copy the zip files to, default: $CFG->tempdir/customlang
 -o, --overwrite         Overwrite existing files in the target folder.
                             Note: If the target is not set, the files are always overwritten!
 -h, --help              Print out this help
@@ -73,9 +73,10 @@ if ($options['help']) {
     echo $usage;
     die;
 }
-if (!file_exists($options['target'])) {
-    mkdir($options['target'], 0777, true);
-}
+
+// Ensure target directory exists.
+$options['target'] = rtrim($options['target'], '/') . '/';
+check_dir_exists($options['target']);
 
 cli_writeln(get_string('cliexportheading', 'tool_customlang'));
 $langs = [];
@@ -90,7 +91,7 @@ foreach ($langs as $lang) {
     $filename = $options['target'] . get_string('exportzipfilename', 'tool_customlang', ['lang' => $lang]);
     // If the file exists and we are not using the temp folder it requires an ovewrite.
     if ($options['target'] != $dafaulttarget && file_exists($filename) && !$options['overwrite']) {
-        cli_problem(get_string('cliexportfileexists', 'tool_customlang', $lang));
+        cli_problem(get_string('cliexportfileexists', 'tool_customlang', ['lang' => $lang]));
         continue;
     }
     cli_heading(get_string('cliexportstartexport', 'tool_customlang', $lang));
diff --git a/admin/tool/customlang/lang/en/tool_customlang.php b/admin/tool/customlang/lang/en/tool_customlang.php
index 9343e68e82e..acb63c43e1a 100644
--- a/admin/tool/customlang/lang/en/tool_customlang.php
+++ b/admin/tool/customlang/lang/en/tool_customlang.php
@@ -50,6 +50,7 @@ $string['customlang:export'] = 'Export local translation';
 $string['customlang:view'] = 'View local translation';
 $string['export'] = 'Export custom strings';
 $string['exportfilter'] = 'Select component(s) to export';
+$string['exportzipfilename'] = 'customlang-export-{$a->lang}.zip';
 $string['editlangpack'] = 'Edit language pack';
 $string['filter'] = 'Filter strings';
 $string['filtercomponent'] = 'Show strings of these components';