After I have logged into the Admin panel, I select configuration, plugins and get the following error:

Server Error in '/' Application.

Must specify valid information for parsing in the string.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ArgumentException: Must specify valid information for parsing in the string.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:


[ArgumentException: Must specify valid information for parsing in the string.]
   System.EnumResult.SetFailure(ParseFailureKind failure, String failureMessageID, Object failureMessageFormatArgument) +4050127
   System.Enum.TryParseEnum(Type enumType, String value, Boolean ignoreCase, EnumResult& parseResult) +9623698
   System.Enum.Parse(Type enumType, String value, Boolean ignoreCase) +80
   System.ComponentModel.EnumConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, Object value) +137

[FormatException:  is not a valid value for TransactMode.]
   System.ComponentModel.EnumConverter.ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, Object value) +456
   Nop.Services.Configuration.ConfigurationProvider`1.<BuildConfiguration>b__6(<>f__AnonymousType2`2 <>h__TransparentIdentifier0) in f:\Own\NopCommerce\Sources\src\Libraries\Nop.Services\Configuration\ConfigurationProvider.cs:31
   System.Linq.<>c__DisplayClass12`3.<CombineSelectors>b__11(TSource x) +20
   System.Linq.WhereSelectEnumerableIterator`2.MoveNext() +151
   System.Collections.Generic.List`1..ctor(IEnumerable`1 collection) +406
   System.Linq.Enumerable.ToList(IEnumerable`1 source) +58
   Nop.Services.Configuration.ConfigurationProvider`1.BuildConfiguration() in f:\Own\NopCommerce\Sources\src\Libraries\Nop.Services\Configuration\ConfigurationProvider.cs:35
   Nop.Services.Configuration.ConfigurationProvider`1..ctor(ISettingService settingService) in f:\Own\NopCommerce\Sources\src\Libraries\Nop.Services\Configuration\ConfigurationProvider.cs:16

[DependencyResolutionException: An exception was thrown while invoking the constructor 'Void .ctor(Nop.Services.Configuration.ISettingService)' on type 'ConfigurationProvider`1'.]
   Autofac.Core.Activators.Reflection.ConstructorParameterBinding.Instantiate() +261
   Autofac.Core.Activators.Reflection.ReflectionActivator.ActivateInstance(IComponentContext context, IEnumerable`1 parameters) +182
   Autofac.Core.Resolving.InstanceLookup.Activate(IEnumerable`1 parameters) +48
   Autofac.Core.Resolving.InstanceLookup.Execute() +48
   Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(ISharingLifetimeScope currentOperationScope, IComponentRegistration registration, IEnumerable`1 parameters) +164
   Autofac.Core.Resolving.InstanceLookup.ResolveComponent(IComponentRegistration registration, IEnumerable`1 parameters) +23
   Autofac.ResolutionExtensions.TryResolveService(IComponentContext context, Service service, IEnumerable`1 parameters, Object& instance) +72
   Autofac.ResolutionExtensions.ResolveService(IComponentContext context, Service service, IEnumerable`1 parameters) +54
   Autofac.ResolutionExtensions.Resolve(IComponentContext context, IEnumerable`1 parameters) +121
   Autofac.ResolutionExtensions.Resolve(IComponentContext context) +52
   Nop.Web.Framework.SettingsSource.<BuildRegistration>b__5(IComponentContext c, IEnumerable`1 p) in f:\Own\NopCommerce\Sources\src\Presentation\Nop.Web.Framework\DependencyRegistrar.cs:279
   Autofac.Builder.<>c__DisplayClass1`1.<ForDelegate>b__0(IComponentContext c, IEnumerable`1 p) +17
   Autofac.Core.Activators.Delegate.DelegateActivator.ActivateInstance(IComponentContext context, IEnumerable`1 parameters) +30
   Autofac.Core.Resolving.InstanceLookup.Activate(IEnumerable`1 parameters) +48
   Autofac.Core.Resolving.InstanceLookup.<Execute>b__6() +12
   Autofac.Core.Lifetime.LifetimeScope.GetOrCreateAndShare(Guid id, Func`1 creator) +106
   Autofac.Core.Resolving.InstanceLookup.Execute() +132
   Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(ISharingLifetimeScope currentOperationScope, IComponentRegistration registration, IEnumerable`1 parameters) +164
   Autofac.Core.Resolving.ResolveOperation.Execute(IComponentRegistration registration, IEnumerable`1 parameters) +70
   Autofac.Core.Lifetime.LifetimeScope.ResolveComponent(IComponentRegistration registration, IEnumerable`1 parameters) +154
   Autofac.ResolutionExtensions.TryResolveService(IComponentContext context, Service service, IEnumerable`1 parameters, Object& instance) +72
   Autofac.ResolutionExtensions.ResolveService(IComponentContext context, Service service, IEnumerable`1 parameters) +54
   Nop.Core.Infrastructure.DependencyManagement.ContainerManager.ResolveUnregistered(Type type) in f:\Own\NopCommerce\Sources\src\Libraries\Nop.Core\Infrastructure\DependencyManagement\ContainerManager.cs:144
   Nop.Core.Plugins.PluginDescriptor.Instance() in f:\Own\NopCommerce\Sources\src\Libraries\Nop.Core\Plugins\PluginDescriptor.cs:96
   Nop.Core.Plugins.PluginDescriptor.Instance() in f:\Own\NopCommerce\Sources\src\Libraries\Nop.Core\Plugins\PluginDescriptor.cs:109
   Nop.Admin.Controllers.PluginController.PreparePluginModel(PluginDescriptor pluginDescriptor) +36
   Nop.Admin.Controllers.PluginController.<List>b__1(PluginDescriptor x) +5
   System.Linq.WhereSelectEnumerableIterator`2.MoveNext() +151
   System.Linq.Buffer`1..ctor(IEnumerable`1 source) +325
   System.Linq.<GetEnumerator>d__0.MoveNext() +96
   System.Collections.Generic.List`1..ctor(IEnumerable`1 collection) +327
   System.Linq.Enumerable.ToList(IEnumerable`1 source) +58
   Nop.Admin.Controllers.PluginController.List() +319
   lambda_method(Closure , ControllerBase , Object[] ) +62
   System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters) +17
   System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) +188
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +27
   System.Web.Mvc.<>c__DisplayClass15.<InvokeActionMethodWithFilters>b__12() +55
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +267
   System.Web.Mvc.<>c__DisplayClass17.<InvokeActionMethodWithFilters>b__14() +20
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodWithFilters(ControllerContext controllerContext, IList`1 filters, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +190
   System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +329
   System.Web.Mvc.Controller.ExecuteCore() +115
   System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +94
   System.Web.Mvc.ControllerBase.System.Web.Mvc.IController.Execute(RequestContext requestContext) +10
   System.Web.Mvc.<>c__DisplayClassb.<BeginProcessRequest>b__5() +37
   System.Web.Mvc.Async.<>c__DisplayClass1.<MakeVoidDelegate>b__0() +21
   System.Web.Mvc.Async.<>c__DisplayClass8`1.<BeginSynchronous>b__7(IAsyncResult _) +12
   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +55
   System.Web.Mvc.<>c__DisplayClasse.<EndProcessRequest>b__d() +31
   System.Web.Mvc.SecurityUtil.<GetCallInAppTrustThunk>b__0(Action f) +7
   System.Web.Mvc.SecurityUtil.ProcessInApplicationTrust(Action action) +23
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +59
   System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +9
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +8970061
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +184

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.272

This is everything from the Stack trace, but I am no programmer. So, can someone out there help me out and explain what I need to do?

Appreciate it.

Phil