Please make sure that in Firefox the Desktop settings are set to view HTML formatted mail: https://www.zimbra.com/desktop2/help/.../z-Setting_your_Desktop_Preferences.htm

Zimbra email has 2 view types; either Adavance View(AJax view) and Standard HTML view Chrome is OK.

But on Firefox get trouble both view type as picture in link.

http://goo.gl/Rf75Ha

Do you have this problem with all HTML-format messages?

In a couple past threads, users reported that HTML messages lost their formatting or even some content. This occurred when the HTML was deeply nested (many layers of tags), which can occur when a message has been forwarded and revised extensively, or sometimes when content is pasted. In those cases, which I don't think involved Zimbra, if the user selected to forward the message to themselves, it would appear normal in the compose window, but when received, it would have the same layout problem.

Does that seem to have any relation to what you're seeing?

Thank you @guigs2 and @jscher2000 for your help.

I think problem was on #firefox ; how is it work different from other Web browser.

If it's #Zimbra's problem, it should was problem on all browser. But now problem was only on #firefox.

In this case, my subordinate sent email directly to my boss and me. He doesn't drag and drop excel file & picture file on email, then sent it. He copied and pasted picture on HTML writing windows on Zimbra email. (on Opera Web Browser) But when I open email on firefox, it 's crash. Open on IE & Chrome is Ok.

Now I corrected this problem indirectly by to change the way that my subordinate sent email. ( To save picture in file and then drag&drop to attached ) But I think it's a problem firefox worse than other browser. ( Now I changed to firefox 36.0 but the problem still occured.

Hi apeng, I don't know why that message is turning to unformatted. Is that happening with all your HTML messages or do you see any pattern to it?

Regarding the crash, Firefox is crashing when you try to view one or more messages? When Firefox crashes, it usually records information about what was happening at that moment. You can submit that data to Mozilla and share it with forum volunteers to see whether it points to the solution. Please check the support article "Firefox Crashes" (especially the last section) for steps to get those crash report IDs, and then post the ones from the relevant time here.

Oh, thank you for the additional information about how the image is dropped into the message. I don't have Zimbra to test with, but someone who does could look at the difference between the messages using those two different techniques and maybe find a clue there.

Do you know what browser your employee was using to create the message?

Firefox doesn't support embedded images via CID (Content-ID) (src="cid:image").