Using CDs copied from the operating system to set up and maintain computers

It is not
permissible to make copies of disks without the permission of their authors,
because of copyright. This is a valid right and it is not permissible to
transgress it, in accordance with the conditions drawn up by both parties. 

It says in
the fatwas of the Standing Committee for Issuing Fatwas, led by Shaykh ‘Abd
al-‘Azeez ibn Baaz: It is not permissible to make copies of programs for
which the authors have not allowed copying, except with their permission,
because the Prophet (peace and blessings of Allaah be upon him) said:
“Muslims are bound by their conditions.” And he (peace and blessings of
Allaah be upon him) said: “A Muslims’ wealth is not permissible unless he
gives it willingly.” And he (peace and blessings of Allaah be upon him)
said: “Whoever reaches a permissible thing first, he has more right to it.”
This applies whether the author of this program is a Muslim or a kaafir who
is not in a state of war with the Muslims, because the rights of a kaafir
who is not in state of war with the Muslims are to be respected like the
rights of a Muslim. And Allaah knows best. End quote from Fataawa
al-Lajnah al-Daa’imah. 

Shaykh
Muhammad ibn Saalih al-‘Uthaymeen (may Allaah have mercy on him) said the
following with regard to this matter: 

This is to
be based on what is known practice (al-‘urf). If a person wants to make a
copy for himself and the original author of the program did not state that
it is not allowed to make copies for personal or public use, then I hope
that there is nothing wrong with it, but if the original author of the
program stated that it is not allowed to make copies for personal or public
use, then it is not permitted at all. End quote. 

Based on
that, it is not permissible to copy the disks for operating systems etc, so
long as the author has not given permission for that.

But if these
disks belong to a company in a state that is at war against the Muslims,
there is nothing wrong with copying them. 

And Allaah
knows best.