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Keep receiving winmail.dat from one client

  • 6 replies
  • 1 has this problem
  • 4 views
  • Last reply by mole_man99

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Before I have to give up on Thunderbird, I would just like to check if my key clients IT dept are correct.

Up to a few weeks ago, I checked email with Thunderbird on win7. All was well.

I swapped to a new drive with fresh install of Win10. I installed latest Thunderbird and Lookout (fix version). All emails come OK, except emails created fresh by my main client, which always come with the signature stripped out and attached as 3 files (winmail.dat, body_part_0.html, body_part_1.vcf)

If I send them an email and they reply, it comes back OK as no signature is added.

I had asked their IT to configure servers to send out HTML. They isist they are, but apparently it is done remotely by their server company who handle the mails.

What puzzles me is why same version of Thunderbird and Lookoutfix on the win7 install displayed their mails correctly.

Could it be a setting of some sort at my end on my new install? I have display message body as original HTML and also display attachments inline both on.

Before I have to give up on Thunderbird, I would just like to check if my key clients IT dept are correct. Up to a few weeks ago, I checked email with Thunderbird on win7. All was well. I swapped to a new drive with fresh install of Win10. I installed latest Thunderbird and Lookout (fix version). All emails come OK, except emails created fresh by my main client, which always come with the signature stripped out and attached as 3 files (winmail.dat, body_part_0.html, body_part_1.vcf) If I send them an email and they reply, it comes back OK as no signature is added. I had asked their IT to configure servers to send out HTML. They isist they are, but apparently it is done remotely by their server company who handle the mails. What puzzles me is why same version of Thunderbird and Lookoutfix on the win7 install displayed their mails correctly. Could it be a setting of some sort at my end on my new install? I have display message body as original HTML and also display attachments inline both on.

All Replies (6)

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There shouldn't be a winmail.dat attachment in the first place. https://support.mozilla.org/en-US/kb/what-winmaildat-attachment

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I had already sent the IT dept that microsoft support article in the hope they could configure their servers, but they insist they are configured correctly and nobody else has an issue.

Before I get forceful with them, I just want to make extra sure it is not my fault. My confidence is knocked as I could open their mail without issue on Thunderbird when on win7. Perhaps win10 is the issue here?

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I had already sent the IT dept that microsoft support article in the hope they could configure their servers

They need to fix their email clients, not the server.

My confidence is knocked as I could open their mail without issue on Thunderbird when on win7.

Thunderbird cannot open winmail.dat attachments, unless the Lookout extension is installed. That's clearly stated in the support article linked above.

Perhaps win10 is the issue here?

No, this has got nothing to do with Win10. Perhaps the Lookout extension isn't installed for Thunderbird on that machine, or the extension doesn't work properly (for whatever reason), or the winmail.dat attachment cannot properly decoded by the extension.

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I had not found that you can access some preferences with lookout addon. Not sure which of these may help.

'Attach MAPI properties' 'Disable Filename Character set Conversion' 'Strict content type matching'

I'll just try some random combo's as they mean little to me.

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mole_man99 said

I had already sent the IT dept that microsoft support article in the hope they could configure their servers, but they insist they are configured correctly and nobody else has an issue.

If you are using Microsoft Outlook, then it is not an issue. the TNEF is a native format for Microsoft outlook. It is only when you leave the cosy walled garden of Microsoft applications that the reality of their use of proprietary protocols and formats sets in.

The IT department obviously took a fob you off approach. Were Microsoft office is deployed in a corporate situation, the corporate IT department makes certain decisions about setting in the deployed software, so they may ultimately be the problem, but they will never admit it.

My experience is that many so called IT experts are not. They a Microsoft experts and when presented with anything that is not bearing a Microsoft logo are of little more use than my grandmother. (She used to change the channels on the TV without a remote).

In this instance you might really do better to ask your correspondent to modify your the entry in their address book to show you do not with to receive TNEF emails as described in the Microsoft article. It is really the line of least resistance. Placing a tick in an address book should not be to hard for even the most hapless of computer users.

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Thanks. I shall work my way around the various contacts and get them to change their Outlook settings.

Slight issue is that emails started off on an iphone by the company MD and sent to me also have the issue. They are going to the central server and having the signature added there, as IT say. Somehow I need to get IT to flag my address on the central server not to receive TNEF, and apparently it can not be done.

Again, I am the only one in the world with this issue, apparently. It is my fault [for not using Microsoft]