What is the best practice to re-index the de-indexed pages due to a bad migration

[riyas_]

Dear Mozers,

We have a Drupal site with more than 200K indexed URLs. Before 6 months a bad website migration happened without proper SEO guidelines. All the high authority URLs got rewritten by the client. Most of them are kept 404 and 302, for last 6 months.

Due to this site traffic dropped more than 80%. I found today that around 40K old URLs with good PR and authority are de-indexed from Google (Most of them are 404 and 302).

I need to pass all the value from old URLs to new URLs.

Example URL Structure
Before Migration (Old)
_http://www.domain.com/2536987_
(Page Authority: 65, HTTP Status:404, De-indexed from Google)

After Migration (Current)
_http://www.domain.com/new-indexed-and-live-url-version_

Does creating mass 301 redirects helps here without re-indexing the old URLS? Please share your thoughts.

• Riyas

[gazzerman1]

Actually we just had this conversation in another Question

http://moz.com/community/q/we-launched-a-new-website-and-organic-search-traffic-disappeared#reply_191599

Try some of the ideas spoken about there?

[riyas_]

OK Gary. Thanks