In my website, most of the pages has a linkedin sharing button written in this way:<li>    <a id=share_linkedin        href=/link/share/linkedin/Dance+Combo+%28Jazz%2C+Tap%2C+Contemporary+Dance%29+%28Age+16+or+above%29        rel=external nofollow        class=share_icon title=LinkedIn target=_blank>        <span></span>    </a></li>I'm sure this is the only code that I use in all the pages for the button.I have also blocked crawling of all the /link/share/ URLs in the robots.txt file.However, I saw many Restricted by robots.txt errors in Google Webmaster. These errors are all associated to /link/share/linkedin/ URLs. Almost every day I got hundreds of such errors, I'm afraid these daily errors will cause negative impact on the ranking of the website.So I'm wonder why google will report error for nofollow links, and what's wrong with my codes?Update: I've got 400 such errors in 4/9/2011 and 370 in 3/9/2011. If there is nothing wrong with the website, then is there an option to get rid of it?
nofollow doesn't stop crawling?
google search console;robots.txt;googlebot;google index;nofollow
According to Google:In general, we don't follow them. This means that Google does not  transfer PageRank or anchor text across these links. Essentially,  using nofollow causes us to drop the target links from our overall  graph of the web. However, the target pages may still appear in our  index if other sites link to them without using nofollow, or if the  URLs are submitted to Google in a Sitemap.Google doesn't gaurentee that they won't crawl the URL, just that the contents won't affect your PageRank. In fact, Wikipedia entry nofollow explicitly claims that Google does crawl nofollow links, but again, doesn't use the contents to affect your PageRank any.The Restricted by robots.txt message is fine--it won't affect your PageRank either. It is informational only.You could drop the external part of the attribute though; using the standard rel=nofollow is probably safer for crawler parsers that aren't as robust.