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Hi Prateek Wow, that's strange that someone should build those links without being hired! I understand if you don't want to change domain and I think that would be a rash move too. I would try and contact the webmasters of the worst links (i.e. from adult sites and the forums that have most spam comments) and ask them if they can remove them. that's going to be a lot of work, but it seems like the only way to get rid of those bad links if you haven't built them. getting better quality links could definitely attenuate the effect of the bad links. but you will run the risk of getting more bad links, yet again! plus, it might become even more obvious to search engines that you are building links manually. so you've got to be really careful here and not build too many at a time and only go for really excellent quality links.