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.ics calendar files showing up as winmail.dat

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  • Last reply by B. R.

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After 20+ years of using Thunderbird I'm about ready to give up on it. My biggest customer sends Teams invites and when I click on the email in Thunderbird 102.4.2 it shows there is a winmail.dat attachment. It does not show the date and time of the meeting.

 I installed LookOut (fix version) and it does change the attachment from winmail.dat to two files: body_part_0.html and body_part_1.ics.  It also adds a bar in the header saying "this message contains an invitation to an event".  But the bar still does nothing to inform me of the date and time of the meeting.  Clicking on the .html shows me how to connect to the meeting, but still no date nor time.  Opening on the .ics file asks which calendar I want to import these items into, but when I click OK to import in my Home calendar it still does not show up on my calendar.  I can manually add it by going to calendar and clicking "event" to fill in all info manually - but I still don't know the date and time of the meeting.
 I've done research on this and apparently my customer could change settings to make it so I don't get their attachments as winmail.dat, but I already asked and that got nowhere.  So don't bother suggesting that I ask my customer to change settings.  I'll switch to another email client if that is the only solution.
 I do know that I can forward the email to my gmail account and it shows the date and time prominently at the top of the email.  That is the only easy way to find the date and time.  I can open the .ics in notepad++ and decode the date and time from UTC, but I'm not interested in doing that for every meeting.
 I don't know if my email server (ionos.com) has done something but I've been putting up with this for months now and have missed many meetings because of it.  Something has to change, and I'm thinking it will be Thunderbird.  I'm willing to spend some time debugging this if someone needs more info, but it is getting old.
After 20+ years of using Thunderbird I'm about ready to give up on it. My biggest customer sends Teams invites and when I click on the email in Thunderbird 102.4.2 it shows there is a winmail.dat attachment. It does not show the date and time of the meeting. I installed LookOut (fix version) and it does change the attachment from winmail.dat to two files: body_part_0.html and body_part_1.ics. It also adds a bar in the header saying "this message contains an invitation to an event". But the bar still does nothing to inform me of the date and time of the meeting. Clicking on the .html shows me how to connect to the meeting, but still no date nor time. Opening on the .ics file asks which calendar I want to import these items into, but when I click OK to import in my Home calendar it still does not show up on my calendar. I can manually add it by going to calendar and clicking "event" to fill in all info manually - but I still don't know the date and time of the meeting. I've done research on this and apparently my customer could change settings to make it so I don't get their attachments as winmail.dat, but I already asked and that got nowhere. So don't bother suggesting that I ask my customer to change settings. I'll switch to another email client if that is the only solution. I do know that I can forward the email to my gmail account and it shows the date and time prominently at the top of the email. That is the only easy way to find the date and time. I can open the .ics in notepad++ and decode the date and time from UTC, but I'm not interested in doing that for every meeting. I don't know if my email server (ionos.com) has done something but I've been putting up with this for months now and have missed many meetings because of it. Something has to change, and I'm thinking it will be Thunderbird. I'm willing to spend some time debugging this if someone needs more info, but it is getting old.

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I am well aware of what winmail.dat files are. And I'm well aware of what causes Thunderbird to show the attachment as winmail.dat. That is of no help in showing the date and time of a meeting in Thunderbird.

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You'll need to tell the sender of the meeting invites to fix their Outlook. Instructions are linked in the article.

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As I already said, can't get my customer to change. Seems most other email programs can handle winmail.dat. If Thunderbird can't then it is time to abandon Thunderbird and get a program that works.