What happened?

After upgrading a multilingual production site from Joomla 5.4.5 to Joomla 6.1.0, the page Extensions -> Update shows the red error message:

Could not fetch update information, enable system debug mode for further information.

This happens when the official language update sites from Accredited Joomla! Translations are enabled.

The issue remains even after the language update site URLs were corrected to translationlist_6.xml and the language packs were manually updated.

If those language update sites are disabled, the red error disappears, but Joomla then shows the yellow warning that some update sites are disabled.

I manually updated/reinstalled the language packs to Joomla 6 compatible versions, but the problem remains.

This appears related to language package update sites after upgrade from J5 to J6.

Related issue:

• #46497 (wrong language update site version after migration)

Steps to reproduce the issue

1. Start with a multilingual Joomla 5.4.5 site.
2. Upgrade the site to Joomla 6.1.0.
3. Go to System -> Update Sites.
4. Ensure the official language update sites (Accredited Joomla! Translations) are enabled.
5. Go to Extensions -> Update.
6. Click Check For Updates.

Version

6.1

Expected result

No red error message should appear.
Joomla should check extension/language updates normally.

Actual result

A red error message appears:

Could not fetch update information, enable system debug mode for further information.

If the official language update sites are disabled, the red error disappears and Joomla only shows the warning that some update sites are disabled.

System Information

• Joomla version: 6.1.0
• PHP version: 8.3.30
• Database: MariaDB 10.11.16
• Web server: LiteSpeed
• Multilingual site: Yes
• Installed languages: English, Ukrainian, Russian, Polish, German, French, Spanish, Dutch, Swedish
• Production site: Yes

Additional Comments

• The issue reproduces on the production server after upgrading from Joomla 5.4.5 to Joomla 6.1.0.
• The problem persists after manually reinstalling/updating the language packs to Joomla 6 compatible versions.
• If the official language update sites (Accredited Joomla! Translations) are disabled, the red error disappears.
• If those language update sites are enabled again, the red error returns.
• This suggests the problem is specifically tied to the official language update sites.