It appears that the archive file is corrupt. I just tried, an I get the same error. I would suggest that you report this error to you SOLIDWORKS Reseller and have them submit an SR for you.
I even tried to open the archive with 7zip and it erred out also.
Charles Mayou | Product Manager - SolidWorks Electrical
Hawk Ridge Systems | The Worldwide #1 SolidWorks Reseller, Authorized Support Provider, and Training Center
575 Clyde Ave, Suite 420 | Mountain View | CA | 94043 | USA
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Thank you Charles I appreciate your suggestion. I'm new to SWE and wondered how to get a support request registered.
Just a quick note, I downloaded one of the "gold" part collections from AB (Rockwell) which also contained several of the same parts from the "silver" collection that I was looking for. If you have Gold access, check out the other part series and see if they have the part you need, those were not corrupt.