I have to yahoo accounts.
The older one always send this errors
[IMAP] Cannot open folder “/Inbox”. (NO [AUTHENTICATIONFAILED] SELECT Invalid credentials)
[IMAP] Cannot open folder “/. Pendientes”. (NO [AUTHENTICATIONFAILED] SELECT Invalid credentials)
[IMAP] Cannot open folder “/Trezor”. (NO [AUTHENTICATIONFAILED] SELECT Invalid credentials)
The other account doesnt send this errors.
Whats the problem???
This is a server error.
Please contact your email provider for assistance.
Ok, but why with the new account i dont have errors and the older one, have lot of errors
That is a question you will need to ask your email provider.
I have the same problem it is with the newest account
[IMAP] Cannot open folder “/Inbox”. (NO [AUTHENTICATIONFAILED] SELECT Invalid credentials)
This is a server error.
Please contact your email provider for assistance.
Gary only say that This is a server error.
Please contact your email provider for assistance.
Dont know what to do
Please contact your email provider for assistance
As @Gary says please contact your email provider for assistance.
So wherever you get your mail from, you need to contact them for assistance. Go to the website where you originally setup your mailbox and contact them. Tell them the error messages.
There is a lot of similar topics about Yahoo account errors, maybe it’s true, it’s a problem with the email provider but also if your read recent comparatives about email clients, it is well known that EmClient encounters problems with the integration of yahoo account 
Maybe all yahoo users need to open a topic in EM Client to know where in yahoo solve this problem or the correct settings to finish this problem.
The topic is already opened. It is this one.
The first step is for you to contact your email provider, because their server is broken.
@cyberzork i allready send an email to yahoo tech support, If I find a solution, I can post it here?
f I find a solution, I can post it here?
Yes if you get a solution to this Yahoo Mail issue post it in this thread.