Moderated and reported by Jim Scheef.
Q – Richard Corzo asked the first question, which we had discussed prior to the meeting: What causes attachments sent by Windows users, mostly using Microsoft Outlook (the “real” Outlook that is included in most versions of Office), to arrive in my inbox transformed into something called “winmail.dat”? We have discussed this recurring problem many times with suggestions to not use Microsoft rich text format (RTF) and instead use HTML or plain text. The problem can appear to be intermittent in that attachments from the same sender will sometimes arrive correctly (for example as a Word document) and other times as winmail.dat. The sender swears that s/he has not changed a thing. This behavior can vary for the same email message between different email clients.
A – We had two immediate solutions. The first was an add-on for Thunderbird called LookOut that decodes the winmail.dat file into the part(s) that make up the attachment(s). The second was an application that works by dropping the winmail.dat file onto the application window and the information is decoded. It turns out there are several of these. We could have “solved” this issue long ago if we had typed “winmail.dat” into Wikipedia. The problem is caused by something called TNEF. From Wikipedia:
Transport Neutral Encapsulation Format or TNEF is a proprietary email attachment format used by Microsoft Outlook and Microsoft Exchange Server. An attached file with TNEF encoding is most often named winmail.dat or win.dat, and has a MIME type of Application/MS-TNEF. The official (IANA) media type, however is application/vnd.ms-tnef.
I realize that description doesn’t help much but I urge readers to peruse the Wikipedia article (wikipedia.org/wiki/Winmail.dat) which includes details beyond the scope of this article. Most useful, however, are the lists of programs that will decode a winmail.dat, or win.dat. Programs are available for Windows, Mac, iOS, Android, UNIX (command line), and several web-based services that require no installation. The Microsoft Knowledgebase Article, “How e-mail message formats affect Internet e-mail messages in Outlook” (support.microsoft.com/kb/290809), includes instructions on how to configure Outlook so that TNEF will not be used. The KB article explains conditions that trigger Outlook to use TNEF, but after reading this section several times, I still do not understand it. The article then gives instructions specific to all versions of Outlook from 2003 and earlier up thru 2013. All involve setting the default message format to HTML or text. Other articles have instructions to edit the Registry.
At the meeting we tried to send a test, which failed miserably due to a comedy of errors on my part. The message never arrived. While writing this, I had Dick Gingras send me a test email from Outlook 2010, formatted in RTF (to force TNEF) with an attached Microsoft Word document. He sent this to four email addresses. I was able to open the attachment using Windows 8 Mail, Yahoo web mail, Windows Live Mail 2011, and Outlook 2013 (of course). I also installed the newest version of Thunderbird and configured it for a couple of email accounts. Naturally the test message opens perfectly without any add-in. We will research this further, but I was unable to make an email that shows the dreaded winmail.dat.
Q – I use the Dropbox cloud service for file storage and have had trouble with the service creating duplicate Excel files. After editing a file, I save it and close Excel. The next day there will be copy-1, copy-2, copy-3. Not all files are duplicated. Is anyone else experiencing this?
A – The suggestion was to check to see if Excel was set to automatically save the file every few minutes. Autosave causing the problem emerged as the primary theory. A member asked if the original file and the copies have different time stamps. This was an excellent question. The files and the copies will all have the same date and time. The original question implies that the duplicates are not seen immediately. When Excel is closed only the original file is in the folder. The duplicates show up the next day. I found a thread on duplicate files in the Dropbox forums and the files were Excel. Coincidence? The person reporting the problem said s/he found over a thousand duplicate files that had accumulated over time. After listening to the discussion and doing some research, my theory is that there is a bug in Dropbox’s synchronization software that gets tripped up when the timing of the autosave function in Excel is close to latency in the synchronization. It’s time to call Dropbox support!
I cannot recall another month when the questions could not be resolved even in post-meeting research.