# Emails are not threaded in Outlook 2013 **URL:** \ **Category:** Bug\ **Created:** [2014年六月13日 04:36 UTC](https://meta.discourse.org/t/emails-are-not-threaded-in-outlook-2013/16501 "2014-06-13T04:36:40Z")\ **Posts on this page:** 1\ **Showing post:** 24
**Author:** ![rumpelsepp](https://avatars.discourse-cdn.com/v4/letter/r/bc79bd/32.png) [@rumpelsepp](https://meta.discourse.org/u/rumpelsepp)\ **Post date:** [2014年十一月26日 10:24 UTC](https://meta.discourse.org/t/emails-are-not-threaded-in-outlook-2013/16501/24 "2014-11-26T10:24:10Z")
Well, it does not really work in every client: Roundcube: ![](https://global.discourse-cdn.com/meta/original/3X/6/3/63ef8903955f5a9998e8a4d7690b18b13f0c602b.png) KMail: ![](https://global.discourse-cdn.com/meta/original/3X/0/2/02d0012f4885f8d3a00ed46e681f13152eccb99a.png) Thunderbird: ![](https://global.discourse-cdn.com/meta/original/3X/1/b/1b6290c8edd3810c67326859492d8ed7d182dcb0.png) Thunderbird seems to grab the "Re: " prefix and the other clients don’t. As the `In-Reply-To` headers are wrong these clients could not do any threading. As mentioned before the specs are here (chapter 3.6.4): [http://www.ietf.org/rfc/rfc2822.txt](http://www.ietf.org/rfc/rfc2822.txt) I have edited the `In-Reply-To` and `References` Headers manually according to the specs. I have replaced these topic links with the appropriate message IDs. Suprise, surprise, it threads well in every client: KMail: ![](https://global.discourse-cdn.com/meta/original/3X/5/6/56c6cc92543382e1d61bc1c3fde84145a000f224.png) Roundcube: ![](https://global.discourse-cdn.com/meta/original/3X/3/1/3134c1b550c2df9d3d3a3d28182a3ee38a139d9c.png) @codinghorror: Have a look at rfc2822 and @peternlewis [post](https://meta.discourse.org/t/emails-are-not-threaded-in-outlook-2013/16501/9) above. That’s the real issue with its intended solution. Adding an `Re:` prefix is just a workaround for some clients. --- _[View the full topic](https://meta.discourse.org/t/emails-are-not-threaded-in-outlook-2013/16501)._