Pligg is a good open source cms available for link sharing kind of stuff.

But the admin interface of pligg is not very advanced so to do many operations on pligg based sites is very difficult.

And the error “Pligg – invalid username or userid in get_avatar” comes when you try to delete disabled users from database.

The first thing is why you are manually trying to delete disabled users from database ?

The frequency of spam user registration is very high. Lots of spam registrations on pligg based sites.

So you disable all spam users and then try to delete manually all disabled users from database.

But before deleting these disabled users from database, delete all spam links submitted by spammers and then proceed futher.

But if you simply delete all users from “pligg_users” database it will create problem.

So same way, by writing some combination of select query, try to get all related comments for those disabled users and then delete them from “pligg_comments” table.

Once you delete those all comments and links from the database then again your site will start working properly.

Let me know, if you have any other simple solution to this problem.

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