Server Error in '/colour-magazine' Application.

Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index

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.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index

Source Error:


Line 284:            
Line 285:            var index = WorldOfColours.FindIndex(x => x == titleId);
Line 286:            var ditem = WorldOfColours[index];
Line 287:            WorldOfColours[index] = WorldOfColours[0];
Line 288:            WorldOfColours[0] = ditem;

Source File: d:\sites\colour-magazine-live\decor.aspx.cs    Line: 286

Stack Trace:


[ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index]
   System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource) +72
   System.Collections.Generic.List`1.get_Item(Int32 index) +4969303
   decor.getSpeciality() in d:\sites\colour-magazine-live\decor.aspx.cs:286
   decor.Page_Load(Object sender, EventArgs e) in d:\sites\colour-magazine-live\decor.aspx.cs:53
   System.Web.UI.Control.OnLoad(EventArgs e) +106
   System.Web.UI.Control.LoadRecursive() +68
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3785


Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.7.3930.0