I upgraded to El Capitain i cannot enter my hotmail e-mail

Hello,

You should not have to manually set an imap path-prefix for Hotmail. If you are sure you have no typos in your hotmail address and password, it's likely that you have two-step verification enabled for your hotmail account. If that's true, you need to log in to Microsoft's website and create an app-specific password for Mail. Also look here: http://windows.microsoft.com/en-us/windows/app-passwords-two-step-verification

In Mail->Preferences->Accounts (2nd tab), when you have already something for hotmail in the list, remove it with the - sign underneath left, then

click the + sign underneath left: in the window that opens, select "other" and fill in all for hotmail.