I found that the topic of the day was rather fitting. Why? Winmail.dat is just stupidly annoying. First, lets go into what causes winmail.dat to occur. Winmail.dat is generated when outlook sends an email as a Rich Text Format. This format is an “outlook” only format and any non-outlook emails receive a winmail.dat message since they don’t play nice with outlook. Basically, Rich Text is like sending emails to an exclusive club and anyone not in it gets the shaft.
Go Microsoft.
The fix? Well, there are a couple of schools of thought. First, you can change it on the client settings. The down and dirty method is to tell all your users that receive this issue to not use Rich Text formatting. Simple right?
The issue. I had a user that uses quickbooks to send out paystubs. Even though she was set to not use Rich Text, the quickbooks integration still did anyways. Nothing like trying to see how much you got paid and you get a winmail.dat instead of your paystub. WEEEEEEEEEE
The solution? Make exchange 2007 NOT use Rich Text formatting. I know, this seems a little extreme, but sometimes you have to go for the gold. Stupid Quickbooks.
Open Exchange Management Console
Expand Organization Configuration
Hub Transport
Edit the default properties
Under Exchange Rich-text format, select Never use.
Problem solved….
June 16th, 2009 at 5:21 pm
Thank you, this helped me very much!
July 20th, 2009 at 11:08 pm
In the first place, God made idiots. That was for practice. Then he made school boards.
September 16th, 2009 at 4:00 am
I found a fix. I tracked it down to the .nk2 file on the sending machines. Potentially this file has been carried forward from prior versions of outlook, or brought over from migrated systems (xp – vista upgrades, etc). On the sending machines, you can delete .nk2 files and have them re-populate correctly, or you can have the sender just remove the entries for receivers complaining of the winmail.dat attachments. It came down to this. If the autocomplete entry in the nk2 file is “common name” for example Ted Jones it will send all emails to a receiving ex2k7 server as text with winmail.dat. If you delete the entry (start typing the email address, select the entry you want to delete and press delete key) and then type it in directly it will re-populate the nk2 file with what the ex2k7 server likes – an nk2 file with only the email address in the autocomplete field (no common name) – example: tedjones@something.com.
You can view the nk2 files with this utility http://www.nirsoft.net/utils/outlook_nk2_autocomplete.html
I tested on two outside sources where they started sending in winmail.dat files after our migration to exchange 2007 (problem did not exist on ex 2003 server).
November 5th, 2009 at 10:36 am
Hi,
This is a nice example of working centralized solution to the issue. Thank You. It is so obvious(ht is responsible for mail delivery), but yet an easy thing to miss, when not managing Exchange 2007 daily.
February 8th, 2010 at 9:06 pm
This worked wonderfully. Thanks so much!