Approval Workflow Error : "An error has occured in Approval"

I have came accross 2 -3 tickets in this week in which the user gets an error in the approval workflow. I knew the solution to it but the user wanted something documented . So tried to check on my blog if i have posted it and found that it was not . so adding to the list .

Issue : Error on Approval Workflow : "An error has occured in Approval"

User has a SharepPoint OOB Approval workflow which can be created through the site and easily be attached to a document library and it starts manually or automatically when a new document gets created and get the required approvers to review and approve the document for publishing.

How to configure a Approval workflow :

For a document library or list

Go to Settings->Workflow Settings->Add Workflow
Choose the Approval workflow from the list, make it start on item creation go to the next page.

Select the approvers and check "Update the approval status"

Click Finish and the workflow is created .

Although this is a easy way to configure the workflow It might end-up with a error:

 Error  System Account :  An error has occured in Approval

A small setting can change the whole error .

This is an approval workflow which should after getting the approvals update the approval status of the document .

The workflow will start and run flawlessly until the end and when it will try to update the approval status.If this setting under Versioning settings is not set  to require content approval it will fail to update the status and thorws the error.

An error has occured in Approval

So, if you come accross an Approval Workflow

Go into the document library settings and go to Versioning Settings Page

Set "Require content approval for submitted items to?"

To Yes and everything should be fine.

This would not make any changes to the Existing status of the workflow . Terminate the workflow and run it again .