Adding the only author of the extension that I could find in Bugzilla as a CC. But it has been almost 3 years since this was last touched, it looks like.

You'll need to get more debugging information than that. Since it's on your localhost, have a look at [[mw:Debugging]] to get some more information on the exact cause of the error.

Felix: If this is still a problem in a supported version of MediaWiki, can you provide more information, as described in comment 2? Thanks in advance!

This looks rather unmaintained, as the Uniwiki extensions listed on http://www.mediawiki.org/wiki/Category:Uniwiki are still in SVN and have not migrated to Git. Might close as WONTFIX.

If you have time, could you please update to a recent supported version (see http://www.mediawiki.org/wiki/Version_lifecycle ) and tell us if this problem still happens?
If this still happens, please add a comment to this report and tell us either your exact software version in case that you know (by updating the "Version" field of this bug report), or on which wiki the problem can be seen. You can find out about your version by going to the Special:Version page, such as https://www.mediawiki.org/wiki/Special:Version .

I set the status of this report to RESOLVED > WORKSFORME for the time being, but feel free to reopen if this problem still happens.

Felix.Wagemakers wrote:

Hello,

I have tested the extension on version Mediawiki 1.22.5 with version Versie 0.3.0 of AutoCreateCategoryPages and it seems to be working fine. So over time the problem was sold.

Greatings

Felix Wagemakers