Description of problem:
SELinux is preventing mktemp from 'write' accesses on the directory /.esmtp_queue.

*****  Plugin restorecon (99.5 confidence) suggests   ************************

If you want to fix the label. 
/.esmtp_queue default label should be default_t.
Then you can run restorecon.
Do
# /sbin/restorecon -v /.esmtp_queue

*****  Plugin catchall (1.49 confidence) suggests   **************************

If you believe that mktemp should be allowed write access on the .esmtp_queue directory by default.
Then you should report this as a bug.
You can generate a local policy module to allow this access.
Do
allow this access for now by executing:
# grep mktemp /var/log/audit/audit.log | audit2allow -M mypol
# semodule -i mypol.pp

Additional Information:
Source Context                system_u:system_r:system_mail_t:s0
Target Context                system_u:object_r:root_t:s0
Target Objects                /.esmtp_queue [ dir ]
Source                        mktemp
Source Path                   mktemp
Port                          <Unknown>
Host                          (removed)
Source RPM Packages           
Target RPM Packages           
Policy RPM                    selinux-policy-3.13.1-128.8.fc22.noarch
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     (removed)
Platform                      Linux (removed) 4.1.3-200.fc22.x86_64 #1 SMP Wed
                              Jul 22 19:51:58 UTC 2015 x86_64 x86_64
Alert Count                   1
First Seen                    2015-08-04 08:26:31 CDT
Last Seen                     2015-08-04 08:26:31 CDT
Local ID                      c878fa6d-49c6-475b-9bdd-4c8814e77cf5

Raw Audit Messages
type=AVC msg=audit(1438694791.57:697): avc:  denied  { write } for  pid=3140 comm="mktemp" name=".esmtp_queue" dev="dm-0" ino=3538945 scontext=system_u:system_r:system_mail_t:s0 tcontext=system_u:object_r:root_t:s0 tclass=dir permissive=0


Hash: mktemp,system_mail_t,root_t,dir,write

Version-Release number of selected component:
selinux-policy-3.13.1-128.8.fc22.noarch

Additional info:
reporter:       libreport-2.6.2
hashmarkername: setroubleshoot
kernel:         4.1.3-200.fc22.x86_64
type:           libreport