SearchEngineJournal.com just published a post entitled “17 Ways to Get De-indexed by Google”

Here are some of the 17 ways,* but you should check out the post which details each of the 17 in-depth:
Cloaking

Duplicate Content

Writing Content with a Machine

Add Unrelated Keywords to Your Content

Joining Link Exchanges and Bad Neighborhoods

Point 100 URLs to One URL

Sending Automated Queries to Google

Scraping Content

Sneaky Redirects

Building Water-thin Affiliate Sites

Duplicate Sites…



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