Support

The Backup on Update feature is a plugin which is shipped with Akeeba Backup Professional (it has been removed from Akeeba Backup Core). When you install the Professional version this plugin is installed and activated.

You either had Akeeba Backup Core installed on those sites or you had disabled the System - Backup on Update plugin yourself. 

If the plugin was just unpublished you just needed to publish it again.

If you had Akeeba Backup Core, in MOST cases you can upgrade to Professional by installing the Professional version once. On very few sites you might have to install the update twice. This is a Joomla bug, nothing we can do about, since it is Joomla's core code which installs the extensions and their updates. I had first seen it around 2007, it's become more frequent since 2013 and I had reported this privately as a bug several times since 2014. I made a public ticket about it in March 2021 when I was told to sod off and my ticket was closed without any work or further reply. It was only ever acknowledged, and only on Twitter and email, by a leadership member (David Jardin, head of JSST) on February 2022 — eight years after I first reported it to Joomla — because it happened to him too, with an extension completely unrelated to ours. Along with the developer of the other extension and my other developer here it's four of us trying to figure out how to reproduce this bloody issue. We still have not found the trigger to it. If we ever do rest assured that we will terminate this bug with extreme prejudice. For now, we know that a necessary but not sufficient condition is that the structure of an extension's root folder must be different (root-level directories must be removed, renamed or added). We expect that for this reason it will not be an issue in Joomla 4 and later versions since the root folder structure remains unchanged between versions.

Regarding the 403, it means that you have either given the wrong Download ID or Joomla forgot about it. See https://www.akeeba.com/news/1746-working-around-joomla-s-broken-extensions-updater.html and our documentation (https://www.akeeba.com/documentation/akeeba-backup-documentation/update.html#update-troubleshooting) for why this happens and what you can do about it. This is another Joomla bug which seems to have been mostly fixed in Joomla 4. At the very least we have not had reports about it in Joomla 4 and we know that its most common root cause has been addressed in Joomla 4, after endless nagging on our part. Joomla 3 is being phased out, don't expect this to ever be fixed there.

So, we have one issue that's either a user error or a Joomla bug and another issue that's a Joomla bug. We can't fix user errors and we are already doing everything in our very limited power to fix the Joomla bugs. Regarding the latter, it's been an uphill battle to have them even acknowledged as bugs by the Joomla project; one took 8 years, the other took 5. I don't know what else you think we can possibly do. We are third party extension developers, we are neither deities nor dictators. That's all we can reasonably do.

> I know that when it goes wrong it is usually when there are multiple updates to perform.

This is actually a very important hint.

There are two ways for download IDs to work in extensions. One is having it in the #__update_sites table, the other is through plugins in the installation folder. The latter is a finicky solution and it is perfectly possible that one plugin gets in the way of another (or in the way of Joomla's built in download ID management with #__update_sites records). When you are updating multiple extensions at once it's possible that an installation plugin overrides the download ID in our downloads, hence the problem.

I had said that this would happen when I saw how the installation plugins were meant to work. Unfortunately, understanding the problem requires having experience troubleshooting this kind of issues, experience in mass distributed software, talking to users like you and being able to think what takes place beyond the code's happy path. I have never seen a core maintainer having all these traits, maybe 2 of these at most. Nor do I expect any maintainer to have these traits because they are incompatible with having the time to be a core maintainer in the first place. What I am trying to do for years is have core maintainers acknowledge that they can't know everything, nor should we expect them to, they need to ask 3PDs who've proven their mettle with core contributions for advice or help. This is changing, however slowly.

Anyway, a moot point now that Joomla 4 exposes the #__update_sites Download Key records in the user interface, rendering the installation plugins obsolete.

> Enabling the plugin is then not enough. I always have to reinstall akeeba, after which the issue is resolved.

This is troubling for two reasons.

First of all, if you are not disabling the plugin and we are not disabling the plugin, who does?

The second and most concerning problem is that enabling doesn't do anything... so you're telling me that its files have been deleted? Do check the folder plugins/system/backuponupdate next time. Is the backuponupdate.php file deleted? If so, you didn't delete it, we didn't delete it, who did?

Do you see why reading this I am very worried? The best case scenario is an extension you use or the host you use is doing something stupid.

> This is a support ticket system and not a bug reporting system.

It is both, by definition. We discover bugs in the course of providing support. Many times what we report as a bug is a limitation we had hit and hadn't found a good way around it at the time. The last several months these are the bulk of the "bugs" I am fixing.

Sure, we have a bug report option in our contact form. 99.5% of the submissions there are users being confused about what they are doing or their host doing something wrong i.e. not a bug. We don't expect to get real bug reports there. We expect users to complain about bogus bugs and we'll point them to the documentation they need to read to understand why it's not and what to do to fix it. It's a public relations tool, not a development one :)