301 Redirects Conflicting W SEO Friendly URLs

[AliseBe]

I've just finished installing PrestaShop v1.5, and now am working with redirecting old pages to knew SEO Friendly URLs generated by PS.  The htaccess redirects work fine for about 75% of the urls, but 25% of the redirects produce errors, such as "product not found".

 

What's really strange about this "product not found" error, is all of these 301 redirects are pointing to category pages, not actual product pages, so there's really no product to find.

 

Whats also really strange is the url produced is a combination of the old url and a new PS friendly url.  For instance if I have an old url like...

 

/pages/boys/batman-muscle-costumes.html, was to point to...

 

http://www.myshop.com/85-batman-costumes, it will actually end up looking like this...

 

http://www.myshop.com/11-costumes-for-boysbatman.html

 

It looks like PS is grabbing the first part of the old url and is trying to match it to new "Costumes-For-Boys" seo friendly url.

 

I have no problem redirecting any urls that don't contain keywords used in new PS urls.  For example, old urls with just product ids redirect perfectly.

 

Is this actually a conflict with PrestaShop, or could it be something else?  Any advise would be greatly appreciated.