If you've lost your sheet templates during the update you may have installed using default settings which may have created a new directory for all the standard templates etc. You can re-direct SolidWorks to your previous files by going into tools>options>default templates and also file locations.
If you've lost your templates you may be able to re-produce them by opening an old file and saving the sheet format.
Is this a question or an answer?
If you've lost your sheet templates during the update you may have installed using default settings which may have created a new directory for all the standard templates etc. You can re-direct SolidWorks to your previous files by going into tools>options>default templates and also file locations.
If you've lost your templates you may be able to re-produce them by opening an old file and saving the sheet format.
hope this is of some help.