xrdp is not accessible with "X server -- no display in range is available" error

From rdp client, it is showing below error:

Checking on the log, this is the error:

$ sudo tail -f  /var/log/xrdp-sesman.log
...
[20150420-09:55:01] [INFO ] scp thread on sck 7 started successfully

[20150420-09:55:02] [INFO ] ++ created session (access granted): username mrapp, ip 10.157.4.55:53456 - socket: 7

[20150420-09:55:02] [INFO ] starting Xvnc session...

[20150420-09:55:02] [ERROR] X server -- no display in range is available

Searching on the web, I stumbled upon a site. Below are the steps that I learned to solve the above issue from the site:

1. Edit /etc/xrdp/sesmain.ini
2. Change MaxSessions from 10 to 100 

$ sudo diff -u {~,/etc/xrdp}/sesman.ini
--- /home/mrapp/sesman.ini      2012-10-29 20:58:30.000000000 +0700
+++ /etc/xrdp/sesman.ini        2015-04-20 09:56:31.277342575 +0700
@@ -13,7 +13,7 @@


 [Sessions]
 X11DisplayOffset=10
-MaxSessions=10
+MaxSessions=100
 KillDisconnected=0
 IdleTimeLimit=0
 DisconnectedTimeLimit=0

3. Restart xrdp

   $ sudo /etc/init.d/xrdp restart

Try to connect with your rdp client, it should work now.