On my new site, the SEOchecker repeated throws 2 errors as below, Anyone knows what I should check for? Many thanks!

SEOChecker: SEOChecker: Error in UrlRewriteComponent for url rewriting

Exception

System.InvalidOperationException: Collection was modified; enumeration operation may not execute. at System.ThrowHelper.ThrowInvalidOperationException(ExceptionResource resource) at System.Collections.Generic.List1.Enumerator.MoveNextRare() at System.Collections.Generic.List1.Enumerator.MoveNext() at SEOChecker.Core.Providers.UrlProviders.UrlRewriteProviders.RewriteUrl(String url, UrlRewriteConfig config) at SEOChecker.Core.Components.UrlRewriteComponent.App_BeginRequest(Object sender, EventArgs e)

SEOChecker: SEOChecker: Error running scheduled task

Exception

System.ArgumentException: Value does not fall within the expected range. at System.Runtime.InteropServices.Marshal.ThrowExceptionForHRInternal(Int32 errorCode, IntPtr errorInfo) at System.Web.Hosting.IIS7WorkerRequest.GetUserAgentInternal() at System.Web.Hosting.IIS7WorkerRequest.GetKnownRequestHeader(Int32 index) at SEOChecker.Core.Umbraco.Context.ContextInfo.Initialize(HttpContext context, Boolean editMode) at SEOChecker.Core.Umbraco.Context.ContextInfo..ctor(HttpContext context) at SEOChecker.Core.Components.ValidationqueueComponent.TimerCallback(Object sender)