Description of problem: When selecting the "Mailer" header in preferences, Evolution crashes
Version-Release number of selected component (if applicable): 3.8.5
Steps to Reproduce:
1) Start Evolution
2) Select Edit -> Preferences
3) Select Mail Preferences
4) Select Headers tab
5) Click on the checkbox by "Mailer"
6) Evolution crashes
Actual results: seg fault
Expected results: Box checked and "X-Mailer" and "User-Agent" headers added to display of messages
Additional info: Originally reported in the CentOS bug tracker as bug 7419
Thanks for a bug report. Could you paste here a backtrace of the crash with a debuginfo package for evolution installed, thus it'll show where exactly evolution crashed, please? Also provide exact package versions, because the "3.8.5" is not going to change any time soon.
To get a backtrace, you can do it like this (after installing the debug info) from a terminal:
$ gdb evolution --ex r --ex bt --ex q
Which will run evolution under gdb, then reproduce the crash, which will print the backtrace and then will try to quit gdb. There will be needed some confirmations, also during the backtrace print, in case it'll be long enough.
Created attachment 920881 [details]
gdb trace with evolution-debuginfo installed
[root@pc65 ~]# rpm -qa evolution\*
The system is a CentOS-7 installed as minimal followed by "yum install evolution".
As a side note, the problem persists even if the system is fully updated
Thanks for the update. I just found an upstream bug report  about the same, which is still opened.
Created attachment 922092 [details]
This fixes the crash. A reproducer:
a) go to Edit->Preferences->Mail Preferences->Headers tab
b) write a new header name
c) click Add button beside the header name
Evolution crashes on NULL dereference.
*** Bug 1128607 has been marked as a duplicate of this bug. ***
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.