The built-in update function introduced in Joomla 2.5 is a great leap forward in simplifying Joomla version maintenance and generally works just fine [1]. Except sometimes, when you know there's a newer version available, but the update checker remains unconvinced.

We just have to provide a little encouragement and everything will be fine.

These examples are from a Joomla 2.5 installation with the Bluestork - Default administration template; I haven't confirmed that the same issue exists in the 3.x series.

The Symptom

On the Control Panel page, the Joomla update checker thinks the Joomla is up to date with version 2.5.17, but I know from other sources that 2.5.20 is available.

Control panel - no updates available

The Resolution

  1. In the update manager (Extensions/Extension Manager) Update manager
  2. Click 'Purge cache' in the toolbar Purge cache button
  3. Which returns an odd message like Purge cache message
    The number of sites enabled may be different.
  4. Back on the Control Panel, the update checker now realises that change is in the air Control panel - updates available
  5. Run the update as usual (click the button) [2] Update message
  6. And then proceed with updating any extensions Control panel - actually up to date

You may want to clear the cache again just in case...

References

1 Of course you still do backups don't you...

2 I really mean it about doing backups.