The manufacturer SEF URLs have /404 appended to them causing 404 errors.
See the URLs in Manufacturer logo module near the bottom of the page at https://www.trendco.co.uk/ (https://www.trendco.co.uk/)
Eg. Noriko image link URL is https://www.trendco.co.uk/shop/manufacturer/noriko/404 but should be https://www.trendco.co.uk/shop/manufacturer/noriko
Disabling Joomla SEF and clearing cache changes the URL to https://www.trendco.co.uk/index.php?option=com_virtuemart&view=category&virtuemart_category_id=0&virtuemart_manufacturer_id=3 - which works correctly.
Note, I published a Redirect in Joomla Redirect Manager for all the manufacturer links as a temporary solution and have just unpublished the one for noriko so that you can see the 404 error. I have cleared the cache.
I have a published menu item of type VirtueMart->Front page on a Hidden Menu.
VirtueMart 'Enable VirtueMart 404 error handling' is disabled.
Using versions: VM 3.0.18 / Joomla 3.6.5
Any ideas please.
I have resolved this. Problem was caused by using the deprecated menu item type VirtueMart - Front page, now changed to VirtueMart Category Layout.
great it was so simple :-) But shows also why the new category view is just superior.