Welcome
this is the log I have when trying to install anything (php5-fpm after removing it)

apt-get install php5-fpm
Reading package lists... Done
Building dependency tree
Reading state information... Done
php5-fpm is already the newest version.
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 php5-fpm (5.4.4-14+deb7u10) ...
insserv: warning: script 'S55IptabLes' missing LSB tags and overrides
insserv: warning: script 'S55IptabLex' missing LSB tags and overrides
insserv: There is a loop between service IptabLes and mountnfs if started
insserv:  loop involving service mountnfs at depth 8
insserv:  loop involving service networking at depth 7
insserv:  loop involving service mountnfs-bootclean at depth 10
insserv: There is a loop between service rc.local and mountall if started
insserv:  loop involving service mountall at depth 6
insserv:  loop involving service checkfs at depth 5
insserv:  loop involving service kbd at depth 11
insserv: There is a loop between service rc.local and mountall-bootclean if started
insserv:  loop involving service mountall-bootclean at depth 7
insserv:  loop involving service urandom at depth 9
insserv: There is a loop between service IptabLes and mountdevsubfs if started
insserv:  loop involving service mountdevsubfs at depth 2
insserv:  loop involving service udev at depth 1
insserv: There is a loop at service rc.local if started
insserv: There is a loop at service IptabLes if started
insserv: Starting IptabLes depends on rc.local and therefore on system facility `$all' which can not be true! (x99 times repeated ) 
insserv: Max recursions depth 99 reached
insserv:  loop involving service postfix at depth 2
insserv: There is a loop between service IptabLes and udev if started
insserv:  loop involving service mountkernfs at depth 1
insserv:  loop involving service IptabLes at depth 1

Now here is the error i get

insserv: exiting now without changing boot order!

    update-rc.d: error: insserv rejected the script header
    dpkg: error processing php5-fpm (--configure):
     subprocess installed post-installation script returned error exit status 1
    Errors were encountered while processing:
     php5-fpm
    E: Sub-process /usr/bin/dpkg returned an error code (1)

The biggest operation I held before this was updating nginx from 1.2 to 1.6 and it was thanks to this site : here is the link : How to upgrade nginx from 1.2 to 1.6 on debian 7

Please help !