There seems to be an issue with Hotmail/Live accounts and emails that have a calendar appointment (.ics) attachment in them.

For Hotmail users: The email is not shown, but the "unread emails" counter does increase.

For Live users: The email preview is shown, and when opened, it has no body, but says something like: open in the original view. If clicked, a calendar appointment is made in Live Calendar, and the email is gone. The contents however is never shown.

This is a part of the original email content:

Content-Type: text/calendar; charset="UTF-8"; method=REQUEST; name=meeting.ics
Content-Disposition: attachment; filename=meeting.ics
BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//VONQ//Qandidate//EN
X-WR-RELCALID:qandidate-9cef927eec6037f4de352e49635c42e0
METHOD:PUBLISH
BEGIN:VEVENT
UID:qandidate-9cef927eec6037f4de352e49635c42e0
DTSTAMP:20180316T092800Z
DTSTART:20180316T092800Z
DTEND:20180316T102800Z
LOCATION:
SUMMARY:Interview: Randy Geraads with VONQ Development
DESCRIPTION:This appointment is managed by Qandidate.com, you cannot make changes\n\nInvitees:\nVONQ Development (*** Email address is removed for privacy ***)\nRandy Geraads (*** Email address is removed for privacy ***)\n
ORGANIZER;CN="VONQ Development":mailto:*** Email address is removed for privacy ***
ATTENDEE;CN="Randy Geraads";CUTYPE=INDIVIDUAL;ROLE=REQ-PARTICIPANT;X-NUM-GUESTS=0:*** Email address is removed for privacy ***
END:VEVENT
END:VCALENDAR

When the same email without the .ics file is sent, all works fine.

Other services (e.g. Gmail) don't have an issue with the .ics file.

What do I need to change (withouth excluding the calendar appointment) in order to see those emails again?

SPAM/Advertising Virus/Spyware/Malware danger Other Term of Use or Code of Conduct violation Child exploitation or abuse Harassment is any behavior intended to disturb or upset a person or group of people. Threats include any threat of suicide, violence, or harm to another. Any content of an adult theme or inappropriate to a community web site. Any image, link, or discussion of nudity. Any behavior that is insulting, rude, vulgar, desecrating, or showing disrespect. Any behavior that appears to violate End user license agreements, including providing product keys or links to pirated software. Unsolicited bulk mail or bulk advertising. Any link to or advocacy of virus, spyware, malware, or phishing sites. Any other inappropriate content or behavior as defined by the Terms of Use or Code of Conduct. Any image, link, or discussion related to child pornography, child nudity, or other child abuse or exploitation.

Hello Randy,

We would like to know more about the issue you're experiencing with email messages with .ICS file attachments. Kindly answer the following questions:

How are you accessing your email messages? Are you using Outlook.com , an Outlook desktop app, or the Mail app?

If you access your email messages through Outlook.com , are you using the classic or Outlook.com beta ?

Is this the first time you encountered the issue?

Is the issue isolated to a single sender?

What troubleshooting steps have you tried so far?

If you're using Outlook.com to view the .ICS file attachments, we advise attaching it as OneDrive link and see if the issue continues. For the steps on how to share files as a OneDrive link, kindly check this support article .

We'll be waiting for your response.

SPAM/Advertising Virus/Spyware/Malware danger Other Term of Use or Code of Conduct violation Child exploitation or abuse Harassment is any behavior intended to disturb or upset a person or group of people. Threats include any threat of suicide, violence, or harm to another. Any content of an adult theme or inappropriate to a community web site. Any image, link, or discussion of nudity. Any behavior that is insulting, rude, vulgar, desecrating, or showing disrespect. Any behavior that appears to violate End user license agreements, including providing product keys or links to pirated software. Unsolicited bulk mail or bulk advertising. Any link to or advocacy of virus, spyware, malware, or phishing sites. Any other inappropriate content or behavior as defined by the Terms of Use or Code of Conduct. Any image, link, or discussion related to child pornography, child nudity, or other child abuse or exploitation.

I am using outlook.com

I use the outlook.com beta, but the same issue appears when reverting to outlook.com classic

It is the first time, but it is not restricted to me. Apparently more @hotmail.com addresses have this issue.

The issue is NOT isolated to a single sender.

Troubleshooting steps:

I sent the email with the .ics attachment to 2 receivers: 1 Hotmail, 1 Gmail.

In Gmail the email appears, in Hotmail it does not. Only the mail counter increases.

I forwarded the same email from Gmail to Hotmail, but the same result appeared.

I forwarded the same email from Gmail to Hotmail, this time without the .ics file. The email appeared in Hotmail.

I downloaded the .ics file and sent it in a new email from Gmail to Hotmail: that email also appeared in Hotmail.

This is part of the source of the attachment:
Content-Type: text/calendar; charset="US-ASCII"; name="meeting.ics"
Content-Disposition: attachment; filename="meeting.ics"
Content-Transfer-Encoding: base64
SPAM/Advertising Virus/Spyware/Malware danger Other Term of Use or Code of Conduct violation Child exploitation or abuse Harassment is any behavior intended to disturb or upset a person or group of people. Threats include any threat of suicide, violence, or harm to another. Any content of an adult theme or inappropriate to a community web site. Any image, link, or discussion of nudity. Any behavior that is insulting, rude, vulgar, desecrating, or showing disrespect. Any behavior that appears to violate End user license agreements, including providing product keys or links to pirated software. Unsolicited bulk mail or bulk advertising. Any link to or advocacy of virus, spyware, malware, or phishing sites. Any other inappropriate content or behavior as defined by the Terms of Use or Code of Conduct. Any image, link, or discussion related to child pornography, child nudity, or other child abuse or exploitation.

Details (required):

We suggest importing or subscribing calendars that can give you an option to import events from an ICS file to your existing calendar. There are third-party calendars that support the ICS file format. Here’s an article that talks about how to import or subscribe to a calendar in Outlook.com.

Let us know if you need additional assistance.

SPAM/Advertising Virus/Spyware/Malware danger Other Term of Use or Code of Conduct violation Child exploitation or abuse Harassment is any behavior intended to disturb or upset a person or group of people. Threats include any threat of suicide, violence, or harm to another. Any content of an adult theme or inappropriate to a community web site. Any image, link, or discussion of nudity. Any behavior that is insulting, rude, vulgar, desecrating, or showing disrespect. Any behavior that appears to violate End user license agreements, including providing product keys or links to pirated software. Unsolicited bulk mail or bulk advertising. Any link to or advocacy of virus, spyware, malware, or phishing sites. Any other inappropriate content or behavior as defined by the Terms of Use or Code of Conduct. Any image, link, or discussion related to child pornography, child nudity, or other child abuse or exploitation.

Details (required):

The issue is not about the calendar, the issue is about emails that should appear in the inbox but do not. It would be less of an issue if porting the meeting to the calendar was not working, but now the entire email with potentially valuable information is not shown. SPAM/Advertising Virus/Spyware/Malware danger Other Term of Use or Code of Conduct violation Child exploitation or abuse Harassment is any behavior intended to disturb or upset a person or group of people. Threats include any threat of suicide, violence, or harm to another. Any content of an adult theme or inappropriate to a community web site. Any image, link, or discussion of nudity. Any behavior that is insulting, rude, vulgar, desecrating, or showing disrespect. Any behavior that appears to violate End user license agreements, including providing product keys or links to pirated software. Unsolicited bulk mail or bulk advertising. Any link to or advocacy of virus, spyware, malware, or phishing sites. Any other inappropriate content or behavior as defined by the Terms of Use or Code of Conduct. Any image, link, or discussion related to child pornography, child nudity, or other child abuse or exploitation.

Details (required):

I have forwarded your concern to our Outlook Team to seek assistance in investigating it. I will get back to you as soon as I receive a response.

If you have other questions or you want to share additional information, feel free to reach out to us. SPAM/Advertising Virus/Spyware/Malware danger Other Term of Use or Code of Conduct violation Child exploitation or abuse Harassment is any behavior intended to disturb or upset a person or group of people. Threats include any threat of suicide, violence, or harm to another. Any content of an adult theme or inappropriate to a community web site. Any image, link, or discussion of nudity. Any behavior that is insulting, rude, vulgar, desecrating, or showing disrespect. Any behavior that appears to violate End user license agreements, including providing product keys or links to pirated software. Unsolicited bulk mail or bulk advertising. Any link to or advocacy of virus, spyware, malware, or phishing sites. Any other inappropriate content or behavior as defined by the Terms of Use or Code of Conduct. Any image, link, or discussion related to child pornography, child nudity, or other child abuse or exploitation.

Details (required):

I have additional information.

I think I found the root cause of the emails not appearing: the contents of the .ics has METHOD:PUBLISH and it is being inserted in the email as METHOD:REQUEST

Changing the contents in the .ics to also being METHOD:REQUEST solved the issue for me.

Looking back it kind of makes sense.

However this solves only part of the issue, because it is still an issue that an email with an "invalid" .ics file is not shown to the recipient.

SPAM/Advertising Virus/Spyware/Malware danger Other Term of Use or Code of Conduct violation Child exploitation or abuse Harassment is any behavior intended to disturb or upset a person or group of people. Threats include any threat of suicide, violence, or harm to another. Any content of an adult theme or inappropriate to a community web site. Any image, link, or discussion of nudity. Any behavior that is insulting, rude, vulgar, desecrating, or showing disrespect. Any behavior that appears to violate End user license agreements, including providing product keys or links to pirated software. Unsolicited bulk mail or bulk advertising. Any link to or advocacy of virus, spyware, malware, or phishing sites. Any other inappropriate content or behavior as defined by the Terms of Use or Code of Conduct. Any image, link, or discussion related to child pornography, child nudity, or other child abuse or exploitation.

Details (required):