in my iphone all seems to work. ...

i can not receive mails

This isn't exactly a comprehensive problem description. You'd need to provide more details about your problem. Please explain

• what you're doing,
• what happens,
• what you expect to happen.

i wanted to read my incoming emails. There were none. I closed Thb, waited 10 sec, openend Thb. Then i got 3 times a message that the certificate is not from a trusted source. see the attachments. When i go to webmail, the mail is there. But it will not arrive in Thb. And it does arrive in my iphone. So it has to do with windows and Thb. I did not change any settings in the accounts.

Later when I tried to solve the problem i took away the V in asking OCSP responderserver.. but the result stayed the same. No income mail.

Generally issues with invalid certificates are caused by antivirus programs using self signed certificates that Thunderbird simply does not support unless you manually add them and direct Thunderbird certificate manager to use them. One of the worst for this is Norton as it has a setting to scan encrypted connections and they interpret this permission for be ALL encrypted communications. Even if you disable email scanning they still scan the data stream, if not the individual emails it contains.

To follow up on Matt's post - what is your anti-virus software?

i took away the V in asking OCSP responderserver.

The problem is almost certainly not related to OCSP.