octobercms/october · error · October\Rain\Exception\ValidationException

Unable to delete site group because it is being used by exis

Error message

Unable to delete site group because it is being used by existing site definitions (:count).

What it means

Error "Unable to delete site group because it is being used by existing site definitions (:count)." thrown in octobercms/october.

Source

Thrown at modules/system/models/SiteGroup.php:67

    public static function syncDefaultGroup()
    {
        if (static::count() > 0) {
            return;
        }

        static::create([
            'name' => 'Default',
            'code' => 'default',
        ]);
    }

    /**
     * beforeDelete
     */
    public function beforeDelete()
    {
        if (($count = $this->sites()->count()) > 0) {
            throw new ValidationException(['name' => __("Unable to delete site group because it is being used by existing site definitions (:count).", ['count' => $count])]);
        }
    }

    /**
     * afterDelete
     */
    public function afterDelete()
    {
        PluginSiteGroup::where('site_group_id', $this->id)->delete();

        Site::resetCache();
    }

    /**
     * afterSave
     */
    public function afterSave()
    {

View on GitHub (pinned to b608633a7e)

When it happens

Trigger: Thrown at modules/system/models/SiteGroup.php:67 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of octobercms/october@b608633a7e (2026-08-21). Data as JSON: /api/errors/7e0c9b23362f3287. Report an issue: GitHub.