SharePoint 2007: Approval Workflow - using SharePoint Groups are Approvers

Recently, I was setting up an Approval workflow. To make administration of the workflow easier, I created SharePoint Groups (e.g. Workflow Approvers), which I assigned as the Approvers of the workflow.

This makes it easier for the Site Administrators to change the Approvers, because they just find the group and edit the members of the group, rather than having to edit the actual workflow.

Strangely, when a workflow was kicked off and a task assigned to the group, once one of the Approvers had approved the item, a task was being set to the System Account user. Thus the approval workflow was not completing.

To solve the issue, you'll need to:
Tick the checkbox "Assign a single task to each group entered (Do not expand groups)” in add a workflow page, no one can be done by any one of participants.

Also check the checkbox Complete this workflow when Following number of tasks are finished and then enter 1 in the text below. This will complete the approval process when one of the user approves it.