Msg#: 4637300 posted 1:36 pm on Jan 16, 2014 (gmt 0)
Google will display the url of pages blocked by robots.txt. They may even show urls that do not exist since they can not crawl the page if it is blocked by robots.txt to discover that it does not exist. This will not impact rankings.
Are these pages blocked by robots.txt or has Google crawled them?
Msg#: 4637300 posted 4:39 pm on Jan 16, 2014 (gmt 0)
Blocking Google from crawling one page will not lower the rankings of your other pages with a few rare exceptions. I would look elsewhere to explain the rankings drop instead of spending time on non-essential pages blocked with robots.txt. That is more of a non-vital cosmetic issue.