The site was created using a quickstart package, unsure if that could be the origin of the issue.
It definitely sounds like it.
id column is an auto–number column, i.e. it's a monotonically increasing database table row counter. You don't give them an explicit value, they get a value automatically when a row is created and it's always the value of the last row created on that table plus one.
I am afraid that your site may be fully broken.
Try creating a new category, article, and module. If you get an error your site is broken. Did you or your host restore a copy of it lately? Did you do any work on the database? This problem happens when someone exports and reimports a database without dumping the schema DDL, i.e. how the tables are created, which was such a common problem back in 2005 that I created the predecessor to our backup software — and the rest, as they say, is history.
If you didn't get an error then only Akeeba Backup is broken. The only simple fix is to lose all your backups and start over. Uninstall Akeeba Backup. Delete all tables with
_akeebabackup_ in their name (if any are left behind). Install Akeeba Backup again.
The hard fix without losing data is to create a new table with the correct schema of the
#__akeebabackup_backups table as we ship it, copy over the data (sans the id value) from the old table to the new, delete the old table, rename the new table to the old name. However, you asked me for a simple fix and this is not it.
Nicholas K. Dionysopoulos
Lead Developer and Director
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