Good morning, When I try to sign in to a (verizon) yahoo e-mail account via Thunderbird, it takes several seconds to get a response, then I often get this error message: ------ Thunderbird The current operation on 'Inbox' did not succeed. The mail server for account [my e-mail account] responded: [CLIENTBUG] SELECT Command is not valid in this state. ------ I then have to exit Thunderbird, and sign in again to all the accounts I want to connect to. I usually have to do this 2-4 times before it finally downloads the folder structure and message headers successfully (though v-e-r-y slowly). I experience this problem randomly but frequently (almost daily) with all 6 of my (verizon) yahoo accounts. My incoming server is set to "imap.mail.yahoo.com:993"; my outgoing server is set to "smtp.mail.yahoo.com:465"; connection security is set to "SSL/TLS". Yahoo e-mail does not work properly in my browser, so that's not a good work-around. I've checked both yahoo and Thunderbird on-line help; I get nothing really helpful, though I notice the problem is not unique to me. What's the real cause of this problem, and what do I fix it? Thank-you for your help. Bill.