[c#] Sequence contains no matching element

I have an asp.net application in which I am using linq for data manipulation. While running, I get the exception "Sequence contains no matching element".

if (_lstAcl.Documents.Count > 0)
{
    for (i = 0; i <= _lstAcl.Documents.Count - 1; i++)
    {
        string id = _lstAcl.Documents[i].ID.ToString();                           
        var documentRow = _dsACL.Documents.First(o => o.ID == id);
        if (documentRow !=null)
        {

            _lstAcl.Documents[i].Read = documentRow.Read;
            _lstAcl.Documents[i].ReadRule = documentRow.ReadRule;

            _lstAcl.Documents[i].Create= documentRow.Create;
            _lstAcl.Documents[i].CreateRule = documentRow.CreateRule;

            _lstAcl.Documents[i].Update = documentRow.Update;
            _lstAcl.Documents[i].UpdateRule = documentRow.UpdateRule;

            _lstAcl.Documents[i].Delete = documentRow.Delete;
            _lstAcl.Documents[i].DeleteRule = documentRow.DeleteRule;
        }
    }
}

Use FirstOrDefault. First will never return null - if it can't find a matching element it throws the exception you're seeing.

_dsACL.Documents.FirstOrDefault(o => o.ID == id);

For those of you who faced this issue while creating a controller through the context menu, reopening Visual Studio as an administrator fixed it.

From the MSDN library:

The First<TSource>(IEnumerable<TSource>) method throws an exception if source contains no elements. To instead return a default value when the source sequence is empty, use the FirstOrDefault method.

Maybe using Where() before First() can help you, as my problem has been solved in this case.

var documentRow = _dsACL.Documents.Where(o => o.ID == id).FirstOrDefault();