Added missing text

Author: ffdixon

_posts/2019-02-14-troubleshooting.md

@@ -476,6 +476,10 @@ E: Sub-process /usr/bin/dpkg returned an error code (1)
 
 In the above example, the `/var/lib/dpkg/info/bbb-client.postinst` failed to finish.  To debug, edit this file and change the first line to read
 
+```
+#!/bin/bash -ex
+```
+
 and run
 
 ```bash
@@ -484,6 +488,7 @@ $ sudo apt-get install -f
 
 You should now see each command in `bbb-conf.postinst` as it executes upto the line in which the error occurs.  Post this output to `https://groups.google.com/forum/#!forum/bigbluebutton-setup` for help in resolving the issue.
 
+
 ### Errors with packages
 
 Some hosting providers do not provide a complete `/etc/apt/source.list`.  If you are finding your are unable to install a package, try replacing your `/etc/apt/sources.list` with the following