Mass Prune Users more than 40,000

[Lynne]

Take a look at your error_logs when you try to delete more than 1000 users and see what the php error is. That is the php variable you will need to modify to be able to remove move than 1000 users at a time. (It isn't a vBulletin variable, it is a server variable you need to modify - probably need to ask your host to modify, that is.)