Why Bing suddenly dropped index of website?

[mcafeeactivatesetups]

Why Bing suddenly dropped index of website? My website indexed in Bing, after some days it dropped index of my website, i dont why? please suggest some idea to re-index it in bing.

[John - Smith]

Why Bing suddenly dropped index of website? My website indexed in Bing, after some days it dropped index of my website, i dont why? please suggest some idea to re-index it in bing.

Any SE will drop or de-index your site if you are doing spamming or involved in spammy activities. So make sure you are not doing Spamming and following SE guidelines.  And if it is de-indexed, resubmit your site.

[Michealyardy]

Change in the Search Engine Ranking Algorithm
Loss of PageRank/Link Popularity
Malware or hаcking
Penalty:-Hidden Text,Artificial Links,Thin Content/Low Quality Pages etc.
Canonicalization Problems
Broken links
Duplicate Content

[kavyasharma561]

You need to check if your webpages have any errors in Bing webmaster tool. Usually search engines de-index webpages when there is an error in the webpage or if it doesn't follow webmaster guidelines.

[hariandro001]

Change in the Search Engine Ranking Algorithm
Loss of PageRank/Link Popularity
Malware or hаcking
Penalty:-Hidden Text,Artificial Links,Thin Content/Low Quality Pages etc.
Canonicalization Problems
Broken links
Duplicate Content

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