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webwoman

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what causes winmail.dat attachments?

This is driving me nuts...

I've check all over MS site, and from their documents it appears to have something to do with how the mail is formatted by the sender. However, I've tried this -- formatted a mail as RTF, than as plaintext, attached the SAME file, gets through just fine. (Outlook 2k). Use Outlook Express, do the same thing, using the same RTF and plaintext formats and the same file, gets through OK. I also had no problem with Outlook 97, 98 or Express from my other machine.

However, other users on our network, using Outlook 98, generate mail that has winmail.dat attachments. From getting these little gems in the past, I know they're encoded -- and not just once, either.

WHY do they get generated? We have one user who saves his files as Word 97 rather than Word2K and then the attached files don't blow up -- but my files NEVER blow up, whether they're Work 2k, PDF, or WordPerfect. Others get WordPerfect files converted to winmail.dat for no apparent reason -- and what's doubly strange is that the person who used to use that machine didn't have any problems.

Is it in how the file is attached? I don't get an option to attach or make an inline attachment, but I know some versions of Outlook (or maybe it's particular settings) do get that... and I know there's an encryption option when you set it up, but that appears to only apply to Personal Folders.

Anybody got any clue? Like I said, a search of MS site doesn't give me much help.. it says that the RTF formatting is the cause, but I sent RTF mail and an attachment just fine from Outlook (to the same person who had trouble with other files/attachments) so I don't think that's it.

I suspect it has to do with HOW the file is attached... but since Outlook has so many @#(%*(#$%*!#$%(* permutations of settings depending on what version and how it was installed (and I think on the phases of the moon as well) I'm not even sure where to look anymore.

Anybody got any ideas? Backed up with documentation would be nice... ;-)
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starl

how are the addresses set up in the address book - there is the option of always sending in rich text format
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ASKER

Yes, I read that. Doesn't seem to make a difference, and e-mail WITHOUT attachments is fine. It's only attachments.

Some people send in RTF, some don't, and it doesn't seem to matter which they choose. It's only ATTACHMENTS that cause the problem.

I thought it was RTF formatting as well, but it's not -- I tested that from my machine using both Outlook and Outlook Express. Didn't make a difference.

I've gotten these on my Netscape mail as well -- and again, it's only when there are ATTACHMENTS that it's a problem. The same person can send mail without attachments and it comes through just fine.

I'm thinking it either has to do with the size of the e-mail or if it's an inline attachment or not....
here's a technical article on how outlook sends messages & attachments. I don't know if it will help you, but since you are looking for info...
http://msdn.microsoft.com/library/psdk/mapi/_mapi1book_attached_files_and_messages.htm
I found that... but it doesn't tell you what settings, what formats, what stupid thing causes that to generate.

I want to know what to change so that it DOESN'T send a winmail.dat file. I've pretty much figured out what the file is.

But thanks for trying.. ;-)
winmail.dat is generated when a user sends a message in Outlook Rich Text format.  This file contains all the rich formatting (fonts, color, size, attachment, form definition, .etc) wrapped into a nice little package that only other Outlook users can decipher.

The recommended way to lose this file is to send a message in Plain Text or HTML*.  Note however that this doesn't always work because Corp/Workgroup users can still override the default message format by marking a contact record to receive outlook rich text only.**  To see if this is what they are doing, open a contact record and double click on the email address.  Uncheck the box to allow the default message format to take precedence.

I hope this helps you...
--
/Neo

* Try to stay away from using Word as the editor as well
** Users can also override message format on a per message basis as well.  For example, the can hand type an email address in the TO line that does not resolve to an address book and then right click on the name and select properties.  Checking the bottom checkbox will generate the winmail.dat file.
neo - but it's not the messages that's the problem - it's the attachments ppl are sending.
For example, if I were to send you an e-mail with an attached word document, that attachment would disappear and be replaced with winmail.dat.

anyway - that's how understand the problem.
attachments do not cause the winmail.dat file to be generated.  It is generated because the message is somehow being TNEF'd.  Most likely cause is that the message is in RTF, they are using Word as the editor, or they have marked a PAB/Contact entry to always receive Rich Text.*

somewhere around here I have a whitepaper from MS that explains message formats and more.  it is very good reading even though it was geared for jar heads.


* Outlook Express is not capable of generating an RTF message.  The menu choice of RTF(HTML) has always been a sore spot with me because it makes recent converts to Outlook think it is the same.  Trust me... it isn't.  OE only does plain text and html and can not generate a winmail.dat, but it was designed to supress the winmail.dat file when it arrives as an attachment.
--
/Neo

PS - There are other reasons why a message will be converted to Rich Text, but this only comes into play when a person connects to Exchange.  If Exchange is in the picture, then there are settings on the server that can impact how others receiving messages.
No. That is NOT it. This ONLY impacts attachments, it has nothing to do with the message itself. We have some users who have no problem, some who do, and both may be using RTF formatting.

Most people have never had a problem, no matter what formatting they use. Others do. Some only SOMETIMES have a problem.

And (again) it's ONLY with attachments. The message itself is fine. I have had times when the message came through as winmail.dat, but not for a long time.

At first I thought it was MIMEd, but it's not -- it's BINARY, not ASCII. I also thought it was a forwarded attachment, but that's not it either -- the last one was an original message, with an attachment (not a large one). AND (again) this same user with the same settings (RTF) had NO problems sending messages WITHOUT attachments.

As a matter of fact, the same COMPUTER had no problems a few weeks ago, so unless the settings were changed somehow (which is possible, we changed mailbox info for a new user) it's not the version of Outlook either.

If it's a settings issue, I just want to know what settings to use to avoid it. If it's an Outlook version issue, then why do some people have the problem, others not, and they can have the same version of Outlook?

But please, don't tell me it's RTF formatting... been there, tried that numerous times.
is there a size limit set on the server? you have said you thought it might be size related - what size files have you tested?
They're little files... nothing large enough to set off the size limit.

Neo, I know what they've written. I don't doubt that in many cases, it's true. However, that's NOT the case this time. RTF was the first thing we checked. Like I said, some people can send attachments with RTF formatting, some can't.

And, as I said before, it's the SAME VERSION that could send them fine before. It's a new USER, and we set up a new mailbox for them, but the software didn't change.

If it's a different way to send attachments, we'll do that. I want to KNOW.

And this is ONLY with attachments -- it's not just any mail.
The only other thing that effect attachment transmission is the way you decide to encode it. (eg. 7 or 8 bit, uuencode, binhex, .etc)  There are servers out there that can not handle certain types of transmissions, but it shouldn't be causing the winmail.dat to be created.

Best suggestion I can give you is try to duplicate the problem and document it.  Contact MS PSS and give them what you have and what you have tried.  If you don't like what you hear from the person, ask for the problem to be escalated.
By the way, what is on the back end (Exchange, Lotus, HP Openmail)  and what mode are the Outlook clients configured in? (All corp/workgroup with Internet Mail service, corp/workgroup w/ Internet Mail service, Internet Mail Only, .etc)
if it's a new user/profile - and only the new user/profile - what kinds of settings are on the exchange server that affect that?

try this:
delete the new profile - copy an existing (working) profile and rename it. I once read an article that this was possible (I'm not exchange admin - so am not sure).
Backend, I'm not so sure... not Exchange, I know. I think it's in the Outlook config -- they're not consistent. Some are corp/workgroup and some are IMO.

Is it possible that one configuration would be fine and one not? We can standardize that (and we're doing that... it just takes a while). If it's going to cause a problem we'll up the priority on that.

It's not just the new user profile... the other times they made some changes (of course, they don't remember what) and it worked. Not everybody is at this location, so I can't physically check the settings for all the machines.
There do seem a lot of probs w/IMO...

I've run out of guesses. My only Q is if the checkbox for sending RTF (you choose that when you create a new pab entry) could be interfering somehow...

It's only attachments, doesn't always happen, there don't seem to be any consistencies... same receivers or different.
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AHA! I'll bet that's it... since the one problem I know about for sure was IMO, and everybody I know for sure works right is corp/workgroup (I came into this in the middle, can't you tell? ;-) )

OK... so we should bump up the priority on getting everybody on corp/workgroup, if for no other reason than to fix this occasional but very frustrating problem.

I'm off this week (yea!) but I'll check it when I get back. I can let my boss know, so she can be on the lookout for it, so we can make a note of their setup.

Still not sure why it would only be on attachments, but that's the best clue I've got so far... and it really does explain a lot (like why I never had problems -- I never set anything up as IMO).

Neo, you get the points... Thanks!

BTW, the next time that comes up, you might want to drop that little gem on them -- it certainly would help in troubleshooting!
>>unless contact record is marked otherwise
so even if you have set the format to plain text, if the contact says rtf it will do that!!?
But that would make sense... the ones with the problems are IMO, and I suspect that the attachment keys something with the format...

And it would also explain why all the corp/workgroup people have no problems -- it doesn't matter what format they check, it's all plaintext anyway.
C/W mode allows you to mark a contact record to receive Outlook Rich Text only. (Causes winmail.dat to be generated)


IMO mode only allows you to mark a contact record to receive plain text.

No, does one mode have more problems that the other.... no.  It is just a pain in <bleep> to support both.  Personally, I'm excited that the next version of Outlook will eliminate this support nightmare.

Cheers...
/Neo

PS - Thanks webwoman for the points.Next time I will ask for operation mode of OL2K before doing any suggesting.
I'm lost. What was the final answer here?

Was the problem solved as I have the exact same problem. I run Exchange Server 2003 and Outlook 2003 on the clients. The emails are arriving to external address with the darn winmail.dat attachment and it seems to strip our original PDF attachment??

Rob
I am lost also, the above comments did not help me. I have Exchagne 2003 with different versions of Outlook. Excel files get stripped out of the email and replaced with winmail.dat
I had a similar problem emailing to Lotus Notes from MS Exchange 2003 and Outlook 2003. I found that I had my default message format set to Rich Text and my editor set to MS Word.

When I was drafting a message to the individual on Lotus Notes, click new message, MS Word would start as the editor, I would then select "Plain Text" as my message format. I would then attach my document (.doc in my case - MIME format), then I would send the message.

I would then find that the person I was sending to got a winmail.dat attachment this the message.

After some investigation, I found that MS Word was not actually converting the message to Plain Text when I selected it from the dropdown menu. In all appearances it was but it was not actually converting it.

Solution: I stopped using MS Word as my editor and changed my default message format to Plain Text.
(Tools->Options->Mail Format:
   Compose in this message format: Plain Text
   Use Microsoft Word 2003 to edit email messages (de-check).

I also setup a contact on the Exchange Server (Active Directory) and set the users message format to MIME: Plain Text (Check Override Internet Mail Service setting for this recipient) under Email Addresses -> Edit-> Advanced.

Thanks -jake.
im a user running outlook 2007 how can I prevent this problem?  i am a hostway customer with a smtp mailbox.  My aol friends are getting winmail.dat files.