I tried the reset, but it didn't help.  Guess I need to get a new mouse.  Thanks.

No, your battery is dead and needs to be replaced. OS X Base System is not a real disk. Make an appointment at the Apple Genius Bar for service. If you need to find an Apple Store - Find a Store - Apple. Or you can buy a battery and replace it yourself. Visit OWC for batteries and tutorials.

If you have the 15" model then chuck it and buy a newer computer.

What happens when you try to add the account back?

Try Mail/Preferences/Accounts /Account Information. Select an account, then go to Outgoing Mail Server (SMTP). From the drop down menu select Edit SMPT server list. See if the account is listed there. If so, delete the SMTP server for the account. Try to add the Mail account again.

Yea, that page is a little tricky. You want it to say 10.13.3 Combo Update at the top and then click Download.

The quick and easy solution (but might not help).

The lengthy PIA procedure (but much more thorough).

Problem solved, thanks to Apple Support.

Hi,

After restoring from a backup, these things tend to happen, especially if you have a large number of apps. I would leave the iPad overnight, and if they are still loading then try deleting the apps and downloading them again. Edit: also, make sure you are connected to WiFi so that the apps can download. 

Hope this helps!

Hello RoninTech,

A dictionary is an unordered collection. It can't be sorted. All you can do is sort the keys and access the values via that array of sorted keys.