sccubs@sccubs-Inspiron-3558:~$ sudo apt-get install virtualbox-5.2
[sudo] password for sccubs:
Reading package lists... Done
Building dependency tree
Reading state information... Done
virtualbox-5.2 is already the newest version (5.2.16-123759~Ubuntu~zesty).
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
1 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] y
Setting up ushare (1.1a-0ubuntu10) ...
/var/lib/dpkg/info/ushare.config: 18: /var/lib/dpkg/info/ushare.config: ifconfig: not found
Job for ushare.service failed because the control process exited with error code.
See "systemctl  status ushare.service" and "journalctl  -xe" for details.
invoke-rc.d: initscript ushare, action "start" failed.
● ushare.service - LSB: uShare
   Loaded: loaded (/etc/init.d/ushare; generated; vendor preset: enabled)
   Active: failed (Result: exit-code) since Mon 2018-07-23 18:55:58 IST; 7ms ago
     Docs: man:systemd-sysv-generator(8)
  Process: 2351 ExecStart=/etc/init.d/ushare start (code=exited, status=2)

Jul 23 18:55:58 sccubs-Inspiron-3558 systemd[1]: Starting LSB: uShare...
Jul 23 18:55:58 sccubs-Inspiron-3558 ushare[2351]: /etc/init.d/ushare: 31: .: Can't open /etc/default/rcS
Jul 23 18:55:58 sccubs-Inspiron-3558 systemd[1]: ushare.service: Control process exited, code=exited status=2
Jul 23 18:55:58 sccubs-Inspiron-3558 systemd[1]: Failed to start LSB: uShare.
Jul 23 18:55:58 sccubs-Inspiron-3558 systemd[1]: ushare.service: Unit entered failed state.
Jul 23 18:55:58 sccubs-Inspiron-3558 systemd[1]: ushare.service: Failed with result 'exit-code'.
dpkg: error processing package ushare (--configure):
 subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
 ushare
E: Sub-process /usr/bin/dpkg returned an error code (1)