Think I might have a solution for everyone. I've been having the exact same error "Sorry, we're having trouble ...". I've done the following:
Opened up a support ticket - they don't seem to know how to support the 10.x software.
Tried to remove the ~/Library/Application Support/Evernote which BTW does not exist.
Deleting the program, empty the trash, reboot and tried to re-install.
Today, I did some poking around to see what files were opened and I found that the "new" location of the files is: ~/Library/Containers/Evernote. To get it to work I did the following:
Signed out of EN app and then quit
Renamed the ~/Library/Containers/Evernote to Evernote-old
Restarted the application and signed back in.
So far - things seem to be working
- Chris