On the Microsoft Dynamics GP Support Blog, Pam Peterson explains a New cost warning in Microsoft Dynamics GP 2010 SP3 for cost variances.
New cost warning in Microsoft Dynamics GP 2010 SP3 for cost variances
Off-Topic & MiscellaneousGP 2010
Archived post from 2012. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.