Any backup, any copy of files...only relates to a previous particular point in time..on a specific system.
If you are referring to data files only (no programs, no O/S), those files present no problem using/viewing on any system, at any time. Data files can be used irrespective of the date on which they are copied.
If you are referring to program files or O/S files...they are of no value at all on a system which is totally different (different motherboard, different drivers, different components) because these files will only perform as they are intended to...where the components are a match for the drivers, settings involved in installing an O/S and/or programs.
I have backups of my current system, made on 20 Sep 2017...a complete backup of my 3 O/Ses (XP, Win 7, Win 10) and the programs installed on each. Those backups are on a FX 8320 system with an Asus motherboard. If I try to restore/use those backups on a Dell Optiplex 755 (another desktop I have), they will not work properly.
I would be able to access any data files included in the backup (videos, music, photos, docuements) but I would not be able to run either XP, Win 7, or Win 10 on a different system, using that backup. Once the system components are changed, the O/S and the programs backed up...are useless and the O/S and all programs expected to work properly...have to be installed.
This is by design...otherwise, users would be able to purchase/install 1 copy of a given O/S and/or programs...on multiple systems with varying hardware. Such would be illegal, if possible, because the licenses for O/Ses and programs are not intended to provide a universal install with a single copy. Those licenses apply to specific systems or a specific number of different systems.
If such were not the case...O/S and program developers would quickly go out of business...and there would be no incentive for anyone to develop products which are marketable/saleable. Users would have to rely on "open-source" and "free" sources for operating systems and the programs which would be useble on a computer, with no support functions and responsibility attendant to the non-sale of those products.
Edited by hamluis, 27 September 2017 - 05:40 AM.