POP Peeper: 3.8.1.0

Webmail: 3.8.0.58

  Login Error ([IN-USE] account is locked by another session or for maintenance, try again.)

I downloaded an email client for my cell phone.  And since I did I can't access my account on my computer.  I can log in via the web on the Windstream site but I can't log in using POP Peeper or Thunderbird.

I can send mail using either of those programs though.

I had my ISP change the password for the account.  I've logged in on my cell phone and then signed out on the cell phone.  Nothing I've tried has worked.  

I have other accounts with the same ISP and all of them work with POP Peeper and Thunderbird.  Only the one that I signed in using myMail app doesn't work.