Hi JimRome,

Please go to Setup, Report and Forms, Statements.

For both the Printer Form Settings and Email Form setting, make sure you select the default form template in the description box.  

If you can click OK and do not receive any invalid file message, it means the default statement is still valid.  You can go back, click the customize from button, customize it through the form designer and save it under a different name to your desktop.

If you still get invalid message even you change it back to the default template, you can go to Control Panel, Programs and Features.  Select your Simply 2010 and click Change.  When you see the Modifying Sage Simply Accounting window, select Update/Reinstall Program.  It will do a repair install of the software including the customized forms.

Hope this helps.