Import customers from .xls file

Our old site was not a osc or zen cart site. I'm not exactly sure how it worked cause I didn't manage it.

I do however have a very long customer list in an excel spreadsheet. How do I go about importing each customer all at once?

I am also busy trying to figure this out. I have exported my customer database from my website to a csv for excell2000 file and added my old database clients into this spreadsheet. I now want to upload this new file to the existing database...
I read somewhere about a mod that can do this and now I can not find it.... can anyone direct me to a way to do this?

as I understand it it will send a welcome email to all... I will just add to it that they have to change the generic password I have given to all to one they specify.

This should work in theory right?

is this something we have to do in phpmyadmin?