I can not upload a lead list. I select the csv list, click next, then make sure all the fields are mapped correctly but when I hit next again, it doesn't do anything. The cancel and back buttons work just fine but the next won't move.
did you try a different browser? or refresh the browser?
Do you have access to import a list?
Besides a different browser, you could try clearing cookies/cache and logging back in.
See if it works then...