支持附件的最普遍可导入的电子邮件文件格式？

Question

I am in the process of creating a webmail export script in PHP. The reason we want to export the e-mails is that we intend to retire the webmail functionality from our site, and we want our users to have access to an archive of their mail.

I have created a script that successfully exports a user's e-mail in the .eml file format, and it works great if the files are imported into Mozilla Thunderbird or Windows Live mail. Microsoft Outlook, however, does not handle the attachments correctly. In Outlook 2007 an attached spreadsheet is not even recognized or displayed at all.

I found this information, which indicates that older versions of Outlook need to be up to date for .eml files to be recognized properly, but the aforementioned results are achieved when using an up to date Windows 7 PC.

My question: Is there a better format for e-mail archive files that will work in Outlook as well as the other most used e-mail software/services?

Answer 1

Outlook should be able to handle EML files just fine. What is the actual MIME header of the MIME part that Outlook cannot handle?

You can also use MSG file format, but it is as binary as it gets, and only Outlook can understand it.