I have a MacBook Pro which I have upgraded to Sierra. Ever since version 45 installed I can not open Thunderbird. I get an error pop up window. I drilled down into the package contents to see what error messages are showing. ABORT: LoadSheetSync failed with error 804b0012 is one. The other message I see is [warn] kq_init: detected broken kqueue; not using.: Undefined error: 0.

I have eight years worth of emails stored in my system and of course, I need to get at an older email but can not.