But upgrading wipes the list ....................... so even for only 28E, that really is the point.
Takes a few seconds and saves hours of grief.
Anyway, if you Google Search for AJ's UK Channel List Openbox/Skybox, you will find.
I shall not Post it here as it resides on other Forums and out of respect we don't copy their material (In the hope we are treated similarly). It comes with Instructions. The last step is to Reboot, or the list will not become active.
Finally as you were supplied the box with a pre-installed list, then a Password may have been applied: That will probably be 3313.
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