I just have a quick question: If I disallow a directory to search engine bots on my site using Disallow: /folder_name/ will this be at all permanent? If I set it now and later want to have that section indexed will simply removing the Disallow line put it completely back to normal or will there be any kind of repercussions? I mean is there anyway it could affect my page rank for pages in the folder that was previously Disallowed? Thanks in advance.
The crawlers will always check your robots.txt before crawling the site, so if the file has change it will use the new rules and have no prefound effect on new pages or directories previously disallowed.