The Court of Appeal ruled that a local man, Daniel Gerber, who claims the solar farm is a blight on the landscape that harms views from his Grade II listed home had left it too late to bring a legal challenge to the grant of planning permission.
As a result they held that the High Court should never have extended time to allow his challenge to proceed.
They overturned last year's decision by Mr Justice Dove and reinstated the planning permission granted by Wiltshire Council in June 2013, under which the solar farm was completed a year later.
The council and solar farm operators Terraform Power and Norrington Solar Farm had taken the matter to the Court of Appeal amid fears it could have cost £1.5 million to dismantle it.
Gerber had claimed he only became aware of the development when the photovoltaic arrays were being installed. At the High Court Mr Justice Dove ruled that he had a "legitimate expectation" that he would be notified of such development proposal near Gifford Hall.
However, Lord Justice Sales today ruled that Gerber was in the same position as anyone else, and that the council had posted notices of the planning application in "prominent places" near the site, including at the end of a lane leading to Gifford Hall, given notice in the local newspaper and put details on its website. As a result, it had met its obligations for publicising the proposal.
Gerber argued that he did not see any of them, but Lord Justice Sales, who was sitting with the Master of the Rolls, Lord Dyson, and Lord Justice Tomlinson said it was "not appropriate to extend time for bringing a legal challenge to the grant of such permission simply because an objector did not notice what was happening".
As a result, he held that the High Court judge had been "wrong" to do so.
He said that Gerber had had a fair opportunity to challenge the decision in good time, that there was "no good excuse" for the delay in bringing proceedings, and that the solar farm owners would suffer "major financial detriment" if the planning permission stayed quashed.
In contrast, Gerber would suffer "less substantial and less significant damage" to his own interests - "principally the harm to amenity he will have to bear as a result of being able to see the solar farm from certain parts of his property, despite a certain amount of screening of the solar farm by trees".
Site operators Norrington Solar Farm and Terraform Power argued at the High Court that the installation cost £10.5 million and that restoration of the site would cost £1.5 million, with only an "uncertain" second hand market for the panels.
R On the Application of Gerber v Wiltshire Council. Case Number: C1/2015/0985