Nintex Workflow 2010: Integer vs Number

What?

A workflow that was built using Nintex Workflow 2010 in SharePoint Server 2010 was working fine for a couple of months and it suddenly started to throw workflow errors.

The workflow was erroring because of a "for each" action that iterates through a collection of integers.

SharePoint 2010 - Internal server error exception: System.ServiceModel.FaultException Microsoft.Office.Server.Search.Query.KeywordQueryInternal.Execute()

What?

You might receive an internal server error exception when you use Search Core / Custom Search Results Web Part in SharePoint 2010 with the below exception in ULS log:

Internal server error exception: System.ServiceModel.FaultException Microsoft.Office.Server.Search.Query.KeywordQueryInternal.Execute()

SharePoint Health Analyzer - The following servers have not executed any timer jobs in the last 2 hours

What?

We have setup a new SharePoint 2010 production farm with 2 web servers. (One WFE and one APP). In the new farm, we have started to see a critical issue in the health analyzer that says "The following servers have not executed any timer jobs in the last 2 hours"

SharePoint 2010: Linq Exception - An item with the same key has already been added.

What?

All of a sudden we started to see a weird exception in our intranet "System.ArgumentException: An item with the same key has already been added." being thrown by a custom web part that shows results that are indexed by SharePoint 2010 Search.