Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

murdoc158

macrumors regular
Original poster
Jan 8, 2007
217
1
West Bend, WI
A co-worker of mine was having problems receiving only winmail.dat attachments on email sent though Outlook. I had the sender cc my email address and was getting the same winmail.dat file. We made some changes to the sender's outgoing Outlook account and I started receiving regular .xls Excel attachments. My co-worker is still getting winmail.dat. I sent an email to him and cc myself and he was able to open the attachment, but then I got the winmail.dat. The previous sender resent to both him and myself and my co-worker got the winmail.dat and I got the attachment just fine.

Does anyone have any idea why the same email will open fine on one machine and not the other, and sporadically at that? We are both using newer Macbook Pros (and fully up to date) and OSX Mail. The emails are being sent from Windows machine running Outlook. Using Outlook OSX on my Macbook gives the same results as OSX Mail.

I'm not looking for work arounds to the problem. We both have the TNEF app to open winmail.dat files and our emails have to be sent in HTML format to keep the corporate email signatures intact and properly formatted.

Any insight is appreciated and as always, thanks in advance.

Edit: If I open the same emails on my Windows machine in Outlook the attachments all work.
 
Last edited:
I cant answer your question but the emails we send out on Macs often produce a blank .htm file on Windows and people always comment "We can't open the second attachment". I have to explain its some kind of invisible file thats become visible. Not sure why it happens, maybe its related to your problem? :confused:
 
Updated first post.

I faced the same issue with my recently bought mbp 15 and 17, one is fine and the other received attachments from pc as winmail.dat, but forwarded the same mail from the winmail.dat mac to another mac, the attachment appeared as normal. resolved it by installing the free application TNEF's enough on the winmail.dat Mac. Try it and see if it works for u, hope it helps.
 
I faced the same issue with my recently bought mbp 15 and 17, one is fine and the other received attachments from pc as winmail.dat, but forwarded the same mail from the winmail.dat mac to another mac, the attachment appeared as normal. resolved it by installing the free application TNEF's enough on the winmail.dat Mac. Try it and see if it works for u, hope it helps.

We both have the TNEF program and it works fine. We are not looking for a work around, just more curious as to why the issue shows up on one email address and not the other, but then affects the other email address and not another at different times.

The issue is not when sending from Mac to Mac. The problem appears to be within Outlook and Exchange and the RTF format. I did some digging though the options on our Exchange server and convinced my supervisor to try disabling Exchange RTF formats completely since Outlook defaults to sending HTML anyway. By doing this Outlook is only left with the options to send as HTML and plain text, both of which formats have been shown to not create the winmail.dat file. I'll report back with our findings.
 
Most e-mail clients do not handle winmail.dat correctly (OS X Mail included). You can avoid this by sending your message as HTML or Plain Text (avoid Rich Text). And if your attaching documents try adding them to a ZIP archive first.

You can also view winmail.dat attachments by forwarding the message to a Gmail account (Gmails web client should let you properly view it).

------

http://support.microsoft.com/kb/278061
http://support.microsoft.com/kb/138053
http://support.apple.com/kb/ht2614
http://www.support.com/blog/post/how-deal-winmaildat-file-attachments
http://jeremy.zawodny.com/blog/archives/009853.html
http://email.about.com/od/outlookti...at_Attachments_from_Being_Sent_in_Outlook.htm
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.