Symptoms
Assume that you install a Microsoft SharePoint Foundation 2010 farm by using Microsoft SQL Server authentication. However, when the SQL Server authentication password is about to expire, there is no way for you to change the password.
Resolution
To resolve this issue, apply the following updates:
2687557 Description of the SharePoint Foundation 2010 hotfix package (Wss-x-none.msp): October 30, 2012
2687545 Description of the SharePoint Server 2010 hotfix package (Coreserver-x-none.msp): November 15, 2012
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.