Export/import members

There's an extension that export and import members? or this have to be made by MySQL?

I have some problems in my old site.

I make a fresh install and import some members, but I have almost 8.000 members and I can import just 7.000 members.

There's a way to do this, that I can import all members?

I am using the version 6.1.6.

Thanks in advance!

Seems after migration works DB clearing. By default it erases members which didn't login 180 days. If u want to keep all users then go admin panel->settings-> DB prunning section and set this option to 0.

Regard