Hi! I have an issue with a lot of duplicated URLs in the Google index and there are strong signs that it is causing SEO problems. I don’t have duplicate links on the site itself, but as it once was set-up, for certain pages the system allows all sorts of variations in the URL. As long as is it has a specific article-id, the same content will be presented under an infinite number of URLs. I guess the duplicates in Googles index has been growing over long time and is due to links gone wrong from other sites that links to mine. The problem is that the system have accepted the variations. Here are examples of variations that exists in the Google index: site.com/a/Cow_Cat/id/5272 site.com/a/cow_cat/id/5272 site.com/a/cow…cat/id/5272 site.com/a/cowcat/id/5272 site.com/a/bird/id/5272 The first URL with mixed case is the syntax used site-wide and for now I have to live with it, it would take too long time to make a change to all lower case. Is it OK for search engines if I set the canonical URL to lower case when the site itself continues to use mixed case? As I understand the very idea with canonical URLs is that you can use them when it is NOT obvious/easy to decide what URL to use and 301 is when it is obvious...but are there any disadvantage? As per now I could easily set canonical URL on each page to lower case but it will take "forever" to change all occurrences on the site itself to lower case. Another question: can htaccess be used for canonical URLs as patterns or can it only done by a rel tag on each page? Thanks!