User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.0.7) Gecko/20060909 Firefox/1.5.0.7 Build Identifier: version 3 alpha 1 (20061006) Using the latest nightly build and a new profile, I try to open an email (the email which I will use as an example has 183KB, as reported by outlook express), which originally has 4 pictures as attachments but thunderbird sees 3, and the third image is not downloaded completely but is truncated at some point. The message in outlook ends with this: qze38l3DGkoG5CeR3oooGmymei+uKUn5cKPqaKKBCfU1PaypFOjurEA5O04NFFAHceKdU8Na7oNt LBeaymtwqEaO9ZZYio7Kw5H0xXD2Ufm3UcJxh2xRRQxrc0L7RZYSWh+dPTvWSylThgQfQ0UVEJNr UupFJ6CGkzRRVmYZzS0UUAFJnHSiigAGDS9qKKACiiigCSJtp5ooooA//9k= ------_=_NextPart_000_01C6E931.841A2977— This is correct. The message in thunderbird ends like this: +Lacf3UgJeeDYX8XwoASn7HTlQBQZViADxPMXppAQXMIBtoezlTgAf6sb762AtbvqoA+eAOR17rn 4muOTrJXGt9BwuaJAnvPeRw91KQG36W17+yiRwMXCdQfbrSkYynEigIKH3koRuURbkDzqHaCoAH5 a1EnmrTut7OVZWsWkDKWom6jcnnWclQEY3 This is wrong, I looked it up in the message outlook downloaded and it is in the middle of the third image. Reproducible: Always Steps to Reproduce: 1. Download any messages containing attachments on this server. Actual Results: Get an incomplete message. Expected Results: Get the original message. I used outlook express 6.00.2900.2180 for comparison, and it downloads the message correctly, so if there is a server bug, it knows how to get around it. I found the same problem on linux using thunderbird 1.5.0.7 build for fedora core 5 x86_64.

DUP of Bug 92111? See also Bug 390795. Anyway, get IMAP protocol log.