I tried to install Regenerate Thumbnails in my newly built WooCommerce site because all the product images are fuzzy. However I received an error message, something about the file did not have a header. Then I tried again and was told the folder already existed and installation failed. I uploaded the ZIP file to my computer and tried it locally but again it failed. How can I successfully install Regenerate Thumbnails?
B Gladstone, Toronto
PS - My site is on a temporary location as it is not "live" yet, so I can't post the link.