Whenever I try to create a new account, enter all the values etc., click the OK button, the window closes (as it is supposed to) but the new account does not appear in the accounts list.

Also, I am not able to create an icon in the navigation bar.

Shutting down and even reinstalling both simple mail and firefox do not help.

All this started - strange enough - when Simple Mail, which worked totally fine a day ago, suddenly disappeared from Firefox.

Error console says:
- SimpleMail is undefined
chrome://simplemail/content/preferences/preferences.xul line: 147
- storage is undefined
chrome://simplemail/content/preferences/preferences.xul line: 226

Still, simple mail appears in firefox' add-on list.

Can you help?
Thanks
Antje