While working on a thorny problem with EPDM and SW BOMs, I discovered the following in the Knowledge Base:

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Solution Id:S-071805

Product:SOLIDWORKS Professional 2016

Created:8/18/2016

Technically Reviewed Date:1/4/2017

Area:Save/Open

Sub-Area:

Question:In the SOLIDWORKS® CAD software, how do I determine if I am using an old template?

Answer:Making sure that you use the correct template version for your version of the SOLIDWORKS® software is fundamental in avoiding unexpected behavior in the Sheet Metal, BOM, Cut List and other environments.

There is no tool available in the user interface to check the template version. One way that you can do this is as follows:

1.     Create a new part or assembly.

2.     Select the 'Top Plane' in the FeatureManager®.

3.     Right-click and select 'Properties'.

The ‘Date created’ field provides information about the creation date. If the template is very old, consider replacing it with a new template from scratch.

As a best practice, you should not save an old template in the latest version of the software. If you create a new part from an old template and then use the ‘Save As’ function to replace the template in the latest release of the SOLIDWORKS CAD software, some internal data does not update properly.

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My problem went away when I saved a new template based on the default SW template over the top of the template that was giving me problems.  So, if you are using Save...As to update your various template files, be aware that problems may occur.