I have upgraded CMS to version 7.1.10 using folder replace method (modules, modulesrepository in VPP folder and modulesbin folder in site root).

Folder replace method was used as we didnt have internet access on our Intranet website.

This process completely worked on my ST machine, but show an error as below on UAT

500: Sequence contains more than one matching element
System.InvalidOperationException: Sequence contains more than one matching element
at System.Linq.Enumerable.SingleOrDefault[TSource](IEnumerable`1 source, Func`2 predicate)
at EPiServer.Packaging.Storage.StateStorage.Load(String packageId, String packageVersion)
at EPiServer.Packaging.SitePackageInfoLoader.GetPackageInfo(IPackage package, IList`1 installedPackages, IList`1 updates, Boolean tryToReload)
at EPiServer.Packaging.SitePackageInfoLoader.<>c__DisplayClassc.b__b(IPackage d)
at System.Linq.Enumerable.WhereSelectListIterator`2.MoveNext()
at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
at EPiServer.Packaging.Packages.SitePackage..ctor(IPackage package, Boolean isModulePackage, Boolean isSystemPackage, Boolean isInstalled, Boolean canBeInstalled, IEnumerable`1 dependencies, IPackage installedPackage, ISitePackage availableUpdate, DateTime installDate, String installedBy)
at EPiServer.Packaging.SitePackageInfoLoader.GetPackageInfo(IPackage package, IList`1 installedPackages, IList`1 updates, Boolean tryToReload)
at EPiServer.Packaging.SitePackageInfoLoader.GetPackageInfo(IPackage package, Boolean tryToReload)
at EPiServer.Packaging.SitePackageManager.GetPackageInfo(IPackage package, Boolean tryToReload)
at System.Linq.Enumerable.WhereSelectListIterator`2.MoveNext()
at NuGet.CollectionExtensions.AddRange[T](ICollection`1 collection, IEnumerable`1 items)
at EPiServer.Packaging.PackageService.GetListingOperationResult(OperationResult`1 getPackagesResult)
at EPiServer.Packaging.UI.Models.PackagesHandler.GetListOfInstalledPackages()
at EPiServer.Packaging.UI.Controllers.EPiAddOnsController.GetInstalledModules()
at lambda_method(Closure , ControllerBase , Object[] )
at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters)
at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
at System.Web.Mvc.ControllerActionInvoker.<>c__DisplayClass13.b__10()
at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation)
at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodWithFilters(ControllerContext controllerContext, IList`1 filters, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
at System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName)
at System.Web.Mvc.Controller.ExecuteCore()
at System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext)
at EPiServer.Shell.Web.Mvc.ModuleMvcHandler.ProcessController(IController controller)
at EPiServer.Shell.Web.Mvc.ModuleMvcHandler.BeginProcessRequest(HttpContextBase httpContext, AsyncCallback callback, Object state)
at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

Pleae help :)