Hello, it looks like we have found the problem: http://www.mail-archive.com/cyrus-devel@lists.andrew.cmu.edu/msg01684.html
We use exactly the cyrus version mentioned in the link, it is not 100% sure if this is the real problem, but we are setting up a server with cyrus 2.4.x and run our tests again. As a simple workaround the option closeFolder=false looks good, we haven't lost a single mail in our testings. Thanks for your time and help, maybe someone will need this information in the future. kind regards, Christoph -- View this message in context: http://camel.465427.n5.nabble.com/MailComponent-MailConsumer-misses-Mails-tp5733010p5737024.html Sent from the Camel - Users mailing list archive at Nabble.com.