I am not sure of the procedure you used to backup the data. If you have used Microsoft backup, you can restore it on any system. Here is the link that helps:
https://support.microsoft.com/en-in/help/17127/windows-back-up-restore
If you used any other method to backup the files, please let me know.
To my understanding, the gateway unit is compaible of support Windows 10. However, if you want the Windows 7 recovery kit, you can try purchasing it from the following weblink:
https://restoredisks.com/find-a-restoredisk/
I am an HP employee.
Regards,
Vidya
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