octobercms/october · error · ApplicationException

Theme [$name] not found

Error message

Theme [$name] not found

What it means

UpdateManager::uninstallTheme() removes a theme via composer and then deletes its directory. It accepts either an October code or a directory name: if CmsTheme::exists($name) fails it retries after themeManager->findDirectoryName($name). If the theme still does not exist, it throws 'Theme [$name] not found' — nothing is installed under that identifier.

Source

Thrown at modules/system/classes/updatemanager/ManagesThemes.php:71

            $composerVersion = $details['composer_version'] ?? '';
        }

        return [$composerCode, $composerVersion];
    }

    /**
     * uninstallTheme attempts to remove the theme using composer before
     * deleting from the filesystem
     */
    public function uninstallTheme($name)
    {
        $themeExists = CmsTheme::exists($name);
        if (!$themeExists) {
            $name = (string) $this->themeManager->findDirectoryName($name);
        }

        if (!CmsTheme::exists($name)) {
            throw new ApplicationException("Theme [$name] not found");
        }

        // Remove via composer
        $composer = ComposerManager::instance();
        $composerCode = $this->themeManager->getComposerCode($name);

        if ($composerCode && $composer->hasPackage($composerCode)) {
            $composer->remove([$composerCode]);
        }

        $this->themeManager->deleteTheme($name);
    }

    /**
     * requestThemeDetails looks up a theme from the update server
     */
    public function requestThemeDetails(string $name): array
    {

View on GitHub (pinned to b608633a7e)

Solutions

1. List the actual directories under /themes and pass the exact one (lowercase, dots converted to dashes, e.g. author-theme)
2. Guard with Cms\Classes\Theme::exists($name) before calling uninstallTheme
3. If the directory is gone but the theme still appears in the backend, refresh/clear the cached theme list so the stale entry disappears
4. For composer-installed themes whose folder is already gone, check composer.json and run composer remove for the package, then delete any leftover directory

Example fix

// before
UpdateManager::instance()->uninstallTheme($name);

// after
if (!\Cms\Classes\Theme::exists($name)) {
    $name = strtolower(str_replace('.', '-', $name));
}
if (\Cms\Classes\Theme::exists($name)) {
    UpdateManager::instance()->uninstallTheme($name);
}

if (!\Cms\Classes\Theme::exists($name)) {
    $name = strtolower(str_replace('.', '-', $name));
}
if (\Cms\Classes\Theme::exists($name)) {
    \UpdateManager::instance()->uninstallTheme($name);
}

try { \UpdateManager::instance()->uninstallTheme($name); } catch (\ApplicationException $ex) { /* treat as already-removed or surface the message */ }

When it happens

Trigger: uninstallTheme('author.theme') when themes/author-theme/ does not exist; calling uninstall twice in a row; passing a display name instead of the code/directory name; the directory was already deleted by hand or by git.

Common situations: Theme folder removed manually while the backend still lists it (stale theme list/record); double-uninstall from the Updates UI; case mismatch between the stored name and the actual directory on a case-sensitive filesystem.

Understand the failure class

Background: 'Could not be found', 'does not exist', 'not found in database': the resource-not-found family when an ID, slug, key, or URI lookup comes back empty — this error's family across 20 libraries.

Related errors

• system::lang.zip.extract_failed
• Values not found for the selected row.
• cms::lang.layout.not_found_name
• cms::lang.cms_object.invalid_file
• cms::lang.cms_object.file_already_exists

AI-assisted analysis of octobercms/october@b608633a7e (2026-08-21). Data as JSON: /api/errors/76cb09d0dd1ce12c. Report an issue: GitHub.