We frequently clean blacklisted websites and submit reconsideration requests to have them de-listed. We have encountered many kinds of blacklist warnings including search engines, anti-virus programs, firewalls and and e-mail spam.
Recently I came across an interesting case where Google was flagging a website due to unwanted software. We were able to get to the bottom of the issue and remove the unwanted malware from the website. In the process we learned a few things and wanted to share them with you as well.