Our blog was hacked last year and a link spam injection code was added to our blog in the process. We have explained it in detail on http://www.alrayeswebsolutions.com/blog/seo/solution-to-the-link-spam-injection-hacking-attack-and-reconsideration-requests-to-google/
We have cleared the blog of all the spam and Google too has reindexed our site and the traffic to the blog has also increased but site hosted on the main domain is affected adversely and there are multiple no. of fake URLs which do not exist and give a 404 are getting indexed and they get reflected as crawl errors in the WMT.
Please guide us as to how we can get rid of these URLs.
When we block the URLs via the robots.txt http://www.alrayeswebsolutions.com/robots.txt and manually remove the URLs from WMT then after some time more of these fake URLs get indexed.
We will be highly obliged if you can help us regarding this.